Biology. California Standards Review Transparencies. Upper Saddle River, New Jersey Boston, Massachusetts

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1 Biology Prentice Hall California Standards Review Transparencies Upper Saddle River, New Jersey Boston, Massachusetts Copyright By Pearson Education, Inc., publishing as Pearson Prentice Hall, Boston, Massachusetts All rights reserved. Printed in the United States of America. This publication is protected by copyright, and permission should be obtained from the publisher prior to any prohibited reproduction, storage in a retrieval system, or transmission in any form or by any means, electronic, mechanical, photocopying, recording, or likewise. The publisher hereby grants permission to reproduce these pages, in part or in whole, for classroom use only, the number not to exceed the number of students in each class. Notice of copyright must appear on all copies. For information regarding permission(s), write to: Rights and Permissions Department, One Lake Street, Upper Saddle River, New Jersey Pearson Prentice Hall is a trademark of Pearson Education, Inc. Pearson is a registered trademark of Pearson plc. ISBN Prentice Hall is a registered trademark of Pearson Education, Inc

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3 CONTENTS To the Teacher VII Correlation of California Biology/Life Science Standards to Standards Review Transparencies IX Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CALIFORNIA BIOLOGY/LIFE SCIENCE REVIEW TRANSPARENCIES Cell Biology Science Content Standard 7 1.c Science Content Standard 7 1.d Science Content Standard 7 1.e Science Content Standard 8 6.b Science Content Standard 8 6.c Biology/Life Science Standard Bl 1.a Biology/Life Science Standard Bl 1.a Biology/Life Science Standard Bl 1.a Biology/Life Science Standard Bl 1.b Biology/Life Science Standard Bl 1.b Biology/Life Science Standard Bl 1.c Biology/Life Science Standard Bl 1.c Biology/Life Science Standard Bl 1.d Biology/Life Science Standard Bl 1.e Biology/Life Science Standard Bl 1.f Biology/Life Science Standard Bl 1.g Biology/Life Science Standard Bl 1.h *Biology/Life Science Standard Bl 1.i *Biology/Life Science Standard Bl 1.j Genetics Science Content Standard 7 2.a Science Content Standard 7 2.a Science Content Standard 7 2.c Science Content Standard 7 2.d Science Content Standard 7 2.e Biology/Life Science Standard Bl 2.a Biology/Life Science Standard Bl 2.b Biology/Life Science Standard Bl 2.c Biology/Life Science Standard Bl 2.d Biology/Life Science Standard Bl 2.e Biology/Life Science Standard Bl 2.f Biology/Life Science Standard Bl 2.g Biology/Life Science Standard Bl 3.a Biology/Life Science Standard Bl 3.a iii

4 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CONTENTS (continued) Biology/Life Science Standard Bl 3.a Biology/Life Science Standard Bl 3.b *Biology/Life Science Standard Bl 3.c *Biology/Life Science Standard Bl 3.d Biology/Life Science Standard Bl 4.a Biology/Life Science Standard Bl 4.a Biology/Life Science Standard Bl 4.b Biology/Life Science Standard Bl 4.c Biology/Life Science Standard Bl 4.c Biology/Life Science Standard Bl 4.c Biology/Life Science Standard Bl 4.d Biology/Life Science Standard Bl 4.e Biology/Life Science Standard Bl 4.f Biology/Life Science Standard Bl 5.a Biology/Life Science Standard Bl 5.a Biology/Life Science Standard Bl 5.a Biology/Life Science Standard Bl 5.b Biology/Life Science Standard Bl 5.b Biology/Life Science Standard Bl 5.c *Biology/Life Science Standard Bl 5.d *Biology/Life Science Standard Bl 5.e Ecology Science Content Standard 6 5.b Science Content Standard 6 5.b Science Content Standard 6 5.c Science Content Standard 6 5.c Science Content Standard 6 5.e Biology/Life Science Standard Bl 6.a Biology/Life Science Standard Bl 6.b Biology/Life Science Standard Bl 6.c Biology/Life Science Standard Bl 6.c Biology/Life Science Standard Bl 6.d Biology/Life Science Standard Bl 6.e Biology/Life Science Standard Bl 6.f *Biology/Life Science Standard Bl 6.g Evolution Science Content Standard 7 3.a Science Content Standard 7 3.b Science Content Standard 7 3.c Biology/Life Science Standard Bl 7.a Biology/Life Science Standard Bl 7.b iv

5 CONTENTS (continued) Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. Biology/Life Science Standard Bl 7.c Biology/Life Science Standard Bl 7.d *Biology/Life Science Standard Bl 7.e *Biology/Life Science Standard Bl 7.f Biology/Life Science Standard Bl 8.a Biology/Life Science Standard Bl 8.b Biology/Life Science Standard Bl 8.c Biology/Life Science Standard Bl 8.d Biology/Life Science Standard Bl 8.e *Biology/Life Science Standard Bl 8.f *Biology/Life Science Standard Bl 8.g Physiology Science Content Standard 7 5.a Science Content Standard 7 5.a Science Content Standard 7 5.c Science Content Standard 7 6.j Biology/Life Science Standard Bl 9.a Biology/Life Science Standard Bl 9.b Biology/Life Science Standard Bl 9.c Biology/Life Science Standard Bl 9.d Biology/Life Science Standard Bl 9.e *Biology/Life Science Standard Bl 9.f *Biology/Life Science Standard Bl 9.g *Biology/Life Science Standard Bl 9.h *Biology/Life Science Standard Bl 9.i Biology/Life Science Standard Bl 10.a Biology/Life Science Standard Bl 10.b Biology/Life Science Standard Bl 10.c Biology/Life Science Standard Bl 10.d Biology/Life Science Standard Bl 10.d Biology/Life Science Standard Bl 10.e *Biology/Life Science Standard Bl 10.f *Biology/Life Science Standard Bl 10.f Investigation and Experimentation Science Content Standard 6IIE 7.c Science Content Standard 6IIE 7.c Science Content Standard 6IIE 7.e Science Content Standard 7IIE 7.c Science Content Standard 8IIE 9.b Science Content Standard 8IIE 9.c Biology/Life Science Standard BlIE 1.a v

6 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CONTENTS (continued) Biology/Life Science Standard BlIE 1.b Biology/Life Science Standard BlIE 1.c Biology/Life Science Standard BlIE 1.d Biology/Life Science Standard BlIE 1.e Biology/Life Science Standard BlIE 1.f Biology/Life Science Standard BlIE 1.g Biology/Life Science Standard BlIE 1.h Biology/Life Science Standard BlIE 1.i Biology/Life Science Standard BlIE 1.j Biology/Life Science Standard BlIE 1.k Biology/Life Science Standard BlIE 1.l Biology/Life Science Standard BlIE 1.m Biology/Life Science Standard BlIE 1.n vi

7 TO THE TEACHER The transparencies in the Prentice Hall Biology: California Standards Review Transparencies book are intended to serve as refreshers of the science content and process skills assessed based on the California Standards Tests. Each transparency focuses on a specific standard for either the High School Life Science (NCLB) or the Biology test. The High School Life Standards are indicated in blue on the transparency. The Table of Contents presents each standard, identified by both topic and number. The correlation on the pages following the Table of Contents gives a complete statement of each standard and the number of each transparency that reviews that standard s content or process skills. Most of the transparencies begin with an illustration or other graphic. Next, the main points of the topic are presented in a bulleted list. Then, each transparency ends with questions for students to answer. The art may support the information in the text, relay information beyond what appears in the text, or supply data that students can use to interpret the text or answer the questions. The questions, in turn, are designed to take students beyond the material in the review points. Some questions require an interpretation of the graphic; others give students an opportunity to exercise critical-thinking skills. You can use these transparencies in several ways: The transparencies lend themselves to whole-class review. You can choose a standard to focus on, project the related transparency, and hold a class discussion on the topic. You can set up the overhead projector with a transparency and leave it projected for a period of time, allowing for independent review of a particular standard. Students can then view the transparency at their convenience. You can arrange for students to view those transparencies that cover standard of particular concern to them. You may wish to let students decide for themselves which topics they need to review. Or you may choose to guide them to particular transparencies you think would be most helpful to them. However you choose to present them, the transparencies are a valuable tool for reviewing the California Biology/Life Science Standards. vii

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9 CORRELATIONS Cell Biology California Biology/Life Science Standards Transparency Grade 7 1. All living organisms are composed of cells, from just one to many trillions, whose details usually are visible only through a microscope. As a basis for understanding this concept: 7.1.c. Students know the nucleus is the repository for genetic information in 1 plant and animal cells. 7.1.d. Students know that mitochondria liberate energy for the work that 2 cells do and that chloroplasts capture sunlight energy for photosynthesis. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. 7.1.e. Students know cells divide to increase their numbers through a process 3 of mitosis, which results in two daughter cells with identical sets of chromosomes. Grade 8 6. Principles of chemistry underlie the functioning of biological systems. As a basis for understanding this concept: 8.6.b Students know that living organisms are made of molecules consisting 4 largely of carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. 8.6.c Students know that living organisms have many different kinds of 5 molecules, including small ones, such as water and salt, and very large ones, such as carbohydrates, fats, proteins, and DNA. Biology/Life Science 1. The fundamental life processes of plants and animals depend on a variety of chemical reactions that occur in specialized areas of the organism s cells. As a basis for understanding this concept: BI.1.a Students know cells are enclosed within semipermeable membranes that 6, 7, 8 regulate their interaction with their surroundings. BI.1.b Students know enzymes are proteins that catalyze biochemical reactions 9, 10 without altering the reaction equilibrium and the activities of enzymes depend on the temperature, ionic conditions, and the ph of the surroundings. BI.1.c Students know how prokaryotic cells, eukaryotic cells (including those 11, 12 from plants and animals), and viruses differ in complexity and general structure. ix

10 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CORRELATIONS California Biology/Life Science Standards Transparency BI.1.d Students know the central dogma of molecular biology outlines the 13 flow of information from transcription of ribonucleic acid (RNA) in the nucleus to translation of proteins on ribosomes in the cytoplasm. BI.1.e Students know the role of the endoplasmic reticulum and Golgi 14 apparatus in the secretion of proteins. BI.1.f Students know usable energy is captured from sunlight by chloroplasts 15 and is stored through the synthesis of sugar from carbon dioxide. BI.1.g Students know the role of the mitochondria in making stored chemical- 16 bond energy available to cells by completing the breakdown of glucose to carbon dioxide. BI.1.h Students know most macromolecules (polysaccharides, nucleic acids, 17 proteins, lipids) in cells and organisms are synthesized from a small collection of simple precursors. BI.1.i Students know how chemiosmotic gradients in the mitochondria and 18 chloroplast store energy for ATP production. BI.1.j Students know how eukaryotic cells are given shape and internal 19 organization by a cytoskeleton or cell wall or both. Genetics Grade 7 2. A typical cell of any organism contains genetic instructions that specify its traits. Those traits may be modified by environmental influences. As a basis for understanding this concept: 7 2.a. Students know the differences between the life cycles and reproduction 20, 21 methods of sexual and asexual organisms. 7 2.c. Students know an inherited trait can be determined by one or more genes d. Students know plant and animal cells contain many thousands of 23 different genes and typically have two copies of every gene. The two copies (or alleles) of the gene may or may not be identical, and one may be dominant in determining the phenotype while the other is recessive. 7 2.e. Students know DNA (deoxyribonucleic acid) is the genetic material of 24 living organisms and is located in the chromosomes of each cell. x

11 CORRELATIONS Biology/Life Science California Biology/Life Science Standards Transparency 2. Mutation and sexual reproduction lead to genetic variation in a population. As a basis for understanding this concept: BI 2.a. Students know meiosis is an early step in sexual reproduction in which 25 the pairs of chromosomes separate and segregate randomly during cell division to produce gametes containing one chromosome of each type. BI 2.b. Students know only certain cells in a multicellular organism undergo 26 meiosis. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. BI 2.c. Students know how random chromosome segregation explains the 27 probability that a particular allele will be in a gamete. BI 2.d. Students know new combinations of alleles may be generated in a zygote 28 through the fusion of male and female gametes (fertilization). BI 2.e. Students know why approximately half of an individual s DNA sequence 29 comes from each parent. BI 2.f. Students know the role of chromosomes in determining an individual s sex. 30 BI 2.g. Students know how to predict possible combinations of alleles in a zygote 31 from the genetic makeup of the parents. 3. A multicellular organism develops from a single zygote, and its phenotype depends on its genotype, which is established at fertilization. As a basis for understanding this concept: BI 3.a. Students know how to predict the probable outcome of phenotypes in a 32, 33, 34 genetic cross from the genotypes of the parents and mode of inheritance (autosomal or X-linked, dominant or recessive). BI 3.b. Students know the genetic basis for Mendel s laws of segregation and 35 independent assortment. *BI 3.c. Students know how to predict the probable mode of inheritance from 36 a pedigree diagram showing phenotypes. *BI 3.d. Students know how to use data on frequency of recombination at 37 meiosis to estimate genetic distances between loci and to interpret genetic maps of chromosomes. xi

12 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CORRELATIONS California Biology/Life Science Standards Transparency 4. Genes are a set of instructions encoded in the DNA sequence of each organism that specify the sequence of amino acids in proteins characteristic of that organisms. As a basis for understanding this concept: BI 4.a. Students know the general pathway by which ribosomes synthesize 38, 39 proteins, using trna to translate genetic information in mrna. BI 4.b. Students know how to apply the genetic coding rules to predict the 40 sequence of amino acids from a sequence of codons in RNA. BI 4.c. Students know how mutations in the DNA sequence of a gene may or 41, 42, 43 may not affect the expression of the gene or the sequence of amino acids in the encoded protein. BI 4.d. Students know specialization of cells in multicellular organisms is 44 usually due to different patterns of gene expression rather than to differences of the genes themselves. BI 4.e. Students know proteins can differ from one another in the number 45 and sequence of amino acids. *BI 4.f. Students know why proteins having different amino acid sequences 46 typically have different shapes and chemical properties. 5. The genetic composition of cells can be altered by incorporation of exogenous DNA into the cells. As a basis for understanding this concept: BI 5.a. Students know the general structures and functions of DNA, RNA, 47, 48, 49 and protein. BI 5.b. Students know how to apply base-pairing rules to explain precise 50, 51 copying of DNA during semiconservative replication and transcription of information from DNA into mrna. BI 5.c. Students know how genetic engineering (biotechnology) is used to 52 produce novel biomedical and agricultural products. *BI 5.d. Students know how basic DNA technology (restriction digestion by 53 endonucleases, gel electrophoresis, ligation, and transformation) is used to construct recombinant DNA molecules. *BI 5.e. Students know how exogenous DNA can be inserted into bacterial cells 54 to alter their genetic makeup and support expression of new protein products. xii

13 CORRELATIONS Ecology California Biology/Life Science Standards Transparency Grade 6 5. Organisms in ecosystems exchange energy and nutrients among themselves and with the environment. As a basis for understanding this concept: 6 5.b. Students know matter is transferred over time from one organism to 55, 56 others in the food web and between organisms and the physical environment. 6 5.c. Students know populations of organisms can be categorized by the 57, 58 functions they serve in an ecosystem. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. 6 5.e. Students know the number and types of organisms and ecosystem can 59 support depends on the resources available and on abiotic factors, such as quantities of light and water, a range of temperatures, and soil composition. Biology/Life Sciences 6. Stability in an ecosystem is a balance between competing effects. As a basis for understanding this concept: BI 6.a. Students know biodiversity is the sum total of different kinds of 60 organisms and is affected by alterations of habitats. BI 6.b. Students know how to analyze changes in an ecosystem resulting from 61 changes in climate, human activity, introduction of nonnative species, or changes in population size. BI 6.c. Students know how fluctuations in population size in an ecosystem are 62, 63 determined by the relative rates of birth, immigration, emigration, and death. BI 6.d. Students know how water, carbon, and nitrogen cycle between abiotic 64 resources and organic matter in the ecosystem and how oxygen cycles through photosynthesis and respiration. BI 6.e. Students know a vital part of an ecosystem is the stability of its 65 producers and decomposers. BI 6.f. Students know at each link in a food web some energy is stored in newly 66 made structures but much energy is dissipated into the environment as heat. This dissipation may be represented in an energy pyramid. *BI 6.g. Students know how to distinguish between the accommodation of an 67 individual organism to its environment and the gradual adaptation of a lineage of organisms through genetic change. xiii

14 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CORRELATIONS Evolution California Biology/Life Science Standards Transparency Grade 7 3. Biological evolution accounts for the diversity of species developed through gradual processes over many generations. As a basis for understanding this concept: 7 3.a. Students know both genetic variation and environmental factors are 68 causes of evolution and diversity of organisms. 7 3.b. Students know the reasoning used by Charles Darwin in reaching this 69 conclusion that natural selection is the mechanisms of evolution. 7 3.c. Students know how independent lines of evidence from geology, fossils, 70 and comparative anatomy provide the bases for the theory of evolution. Biology/Life Science 7. The frequency of an allele in a gene pool of a population depends on many factors and may be stable or unstable over time. As a basis for understanding this concept: BI 7.a. Students know why natural selection acts on the phenotype rather than 71 the genotype of an organism. BI 7.b. Students know why alleles that are lethal in a homozygous individual 72 may be carried in a heterozygote and thus maintained in a gene pool. BI 7.c. Students know new mutations are constantly being generated in a 73 gene pool. BI 7.d. Students know variation within a species increases the likelihood that 74 at least some members of a species will survive under changed environmental conditions. *BI 7.e. Students know the conditions for Hardy-Weinberg equilibrium in a 75 population and why these conditions are not likely to appear in nature. *BI 7.f. Students know how to solve the Hardy-Weinberg equation to predict the 76 frequency of genotypes in a population, given the frequency of phenotypes. 8. Evolution is the result of genetic changes that occur in constantly changing environments. As a basis for understanding this concept: BI 8.a. Students know how natural selection determines the differential 77 survival of groups of organisms. xiv

15 CORRELATIONS California Indiana Biology/Life Academic Standards: Science Standards Biology Transparency BI 8.b. Students know a great diversity of species increases the chance 78 that at least some organisms survive major changes in the environment. BI 8.c. Students know the effects of genetic drift on the diversity of 79 organisms in a population. BI 8.d. Students know reproductive or geographic isolation affects speciation. 80 BI 8.e. Students know how to analyze fossil evidence with regard to 81 biological diversity, episodic speciation, and mass extinction. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. *BI 8.f. Students know how to use comparative embryology, DNA or 82 protein sequence comparisons, and other independent sources of data to create a branching diagram (cladogram) that shows probable evolutionary relationships. *BI 8.g. Students know how several independent molecular clocks, 83 calibrated against each other and combined with evidence from the fossil record, can help to estimate how long ago various groups or organisms diverged evolutionarily from one other. Physiology Grade 7 5. The anatomy and physiology of plants and animals illustrate the complementary nature of structure and function. As a basis for understanding this concept: 7 5.a. Students know plants and animals have levels of organization for 84, 85 structure and function, including cells, tissues, organs, organ systems, and the whole organism. 7 5.c. Students know how bones and muscles work together to provide a 86 structural framework for movement. 7 6.j. Students know that contractions of the heart generate blood pressure 87 and that heart valves prevent backflow of blood in the circulatory system. Biology/Life Science 9. As a result of the coordinated structures and functions of organ systems, the internal environment of the human body remains relatively stable (homeostatic) despite changes in the outside environment. As a basis for understanding this concept: xv

16 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CORRELATIONS California Biology/Life Science Standards Transparency BI 9.a. Students know how the complementary activity of major body systems 88 provides cells with oxygen and nutrients and removes toxic waste products such as carbon dioxide. BI 9.b. Students know how the nervous system mediates communication 89 between different parts of the body and the body s interactions with the environment. BI 9.c. Students know how feedback loops in the nervous and endocrine 90 systems regulate conditions in the body. BI 9.d. Students know the functions of the nervous system and the role of 91 neurons in transmitting electrochemical impulses. BI 9.e. Students know the roles of sensory neurons, interneurons, and motor 92 neurons in sensation, thought and response. *BI 9.f. Students know the individual functions and sites of secretions of 93 digestive enzymes (amylases, proteases, nucleases, lipases), stomach acid, and bile salts. *BI 9.g. Students know the homeostatic role of the kidneys in the removal 94 of nitrogenous wastes and the role of the liver in blood detoxification and glucose balance. *BI 9.h. Students know the cellular and molecular basis of muscle contraction, 95 including the roles of actin, myosin, Ca +2, and ATP. *BI 9.i. Students know how hormones (including digestive, reproductive, 96 osmoregulatory) provide internal feedback mechanisms for homeostasis at the cellular level and in whole organisms. 10. Organisms have a variety of mechanisms to combat disease. As a basis for understanding the human immune response: BI 10.a. Students know the role of the skin in providing nonspecific defenses 97 against infection. BI 10.b. Students know the role of antibodies in the body s response to infection. 98 BI 10.c. Students know how vaccinations protect an individual from 99 infectious diseases. xvi

17 CORRELATIONS California Biology/Life Science Standards Transparency BI 10.d. Students know there are important differences between bacteria and 100, 101 viruses with respect to their requirements for growth and replication, the body s primary defenses against bacterial and viral infections, and effective treatments of these infections. BI 10.e. Students know why an individual with a compromised immune 102 system (for example, a person with AIDS) may be unable to fight off and survive infections by microorganisms that are usually benign. *BI 10.f. Students know the roles of phagocytes, B-lymphocytes, and 103, 104 T-lymphocytes in the immune system. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. Investigation and Experimentation Grade 6 7. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other three strands, students should develop their own questions and perform investigations. Students will: 6IIE 7c. Construct appropriate graphs from data and develop qualitative 105, 106 statements about the relationships between variables. 6IIE 7e. Recognize whether evidence is consistent with a proposed explanation. 107 Grade 7 7. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other three strands, students should develop their own questions and perform investigations. Students will: 7IIE 7.c. Communicate the logical connections among hypotheses, science 108 concepts, tests conducted, data collected, and conclusions drawn from the scientific evidence. Grade 8 9. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other three strands, students should develop their own questions and perform investigations. Students will: 8IIE 9.b. Evaluate the accuracy and reproducibility of data IIE 9.c. Distinguish between variable and controlled parameters in a test. 110 xvii

18 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. CORRELATIONS California Biology/Life Science Standards Biology/Life Science Transparency 1. Scientific progress is made by asking meaningful questions and conducting careful investigations. As a basis for understanding this concept and addressing the content in the other four strands, students should develop their own questions and perform investigations. Students will: BIIE 1.a. Select and use appropriate tools and technology (such as computer- 111 linked probes, spreadsheets and graphing calculators) to perform tests, collect data, analyze relationships, and display data. BIIE 1.b. Identify and communicate sources of unavoidable 112 experimental errors. BIIE 1.c. Identify possible reasons for inconsistent results, such as sources of 113 error or uncontrolled conditions. BIIE 1.d. Formulate explanations by using logic and evidence. 114 BIIE 1.e. Solve scientific problems by using quadratic equations and simple 115 trigonometric, exponential, and logarithmic functions. BIIE 1.f. Distinguish between hypothesis and theory as scientific terms. 116 BIIE 1.g. Recognize the usefulness and limitations of models and theories as 117 scientific representations of reality. BIIE 1.h. Read and interpret topographic and geologic maps. 118 BIIE 1.i. Analyze the locations, sequences, or time intervals that are 119 characteristic of natural phenomena (e.g. relative ages of rocks, locations of planets over time, and succession of species in an ecosystem). BIIE 1.j. Recognize the issues of statistical variability and the need for 120 controlled tests. BIIE 1.k. Recognize the cumulative nature of scientific evidence. 121 BIIE 1.l. Analyze situations and solve problems that require combining and 122 applying concepts from more than one area of science. xviii

19 CORRELATIONS Cell Transparency BIIE 1.m. Investigate a science-based societal issue by researching the 123 literature, analyzing data, and communicating the findings. Examples of issues include irradiation of food, cloning of animals by somatic cell nuclear transfer, choice of energy sources, and land and water use decisions in California. BIIE 1.n. Know that when an observation does not agree with an accepted 124 scientific theory, the observation is sometimes mistaken or fraudulent (e.g., the Piltdown Man fossil or unidentified flying objects) and that the theory is sometimes wrong (e.g., Ptolemaic model of the movement of the Sun, Moon, and planets). Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. xix

20 Cell Biology 1 California Biology/Life Science Standard 7 1.c Chloroplast Cell membrane Cell wall Golgi apparatus Vacuole Mitochondrion Plant Cell Smooth endoplasmic reticulum Ribosome (free) Ribosome (attached) Nuclear envelope Nucleolus Nucleus Rough endoplasmic reticulum The nucleus controls most cell processes and contains nearly all the cell s DNA. The nucleus is surrounded by a nuclear envelope. Most nuclei contain a small dense region called the nucleolus where the assembly of ribosomes begins. Nuclear envelope Rough endoplasmic reticulum Golgi apparatus Nucleolus Nucleus Animal Cell 4819_BI6E_SENA_U03C07_V1 3/9/01 Ribosome (attached) Ribosome (free) Cell membrane Mitochondrion Smooth endoplasmic reticulum Centrioles 1. Where is the genetic material located in a eukaryotic cell? 2. Which type of organelle assembles proteins? 3. What structures do plant cells have that animal cells do not? 1. In the nucleus 2. Ribosomes 3. A cell wall, a vacuole, and chloroplasts

21 Cell Biology 2 California Biology/Life Science Standard 7 1.d Light H2O Light- Dependent Reactions NADP+ ADP + P ATP NADPH CO2 Calvin Cycle Chloroplast O2 Sugars Most cells get energy either from the Sun or from food molecules. Mitochondria are organelles that convert the chemical energy stored in food into compounds that are more convenient for the cell to use. Chloroplasts are organelles that capture energy from sunlight to convert carbon dioxide and water into oxygen and sugars. 1. Do animal cells contain chloroplasts? Explain your answer. 2. What two reactions take place inside the chloroplasts? 1. No, animals do not carry out photosynthesis. 2. The light-dependent reactions and the Calvin cycle

22 Cell Biology 3 California Biology/Life Science Standard 7 1.e 1 INTERPHASE 2 A MITOSIS: Prophase 3 CYTOKINESIS 2 B MITOSIS: Metaphase 2 D MITOSIS: Telophase 2 C MITOSIS: Anaphase During the cell cycle, a cell grows and prepares for division. It divides to form two identical daughter cells, each of which then begins the cycle again. All organisms begin their life cycles as a single cell. Most unicellular organisms reproduce asexually by a form of mitosis called binary fission. In multicellular organisms, successive generations of embryonic cells form by cell division. 1. What is DNA replication? During which stage of the cell cycle does it occur? 2. During which phase of mitosis do the chromosomes line up across the center of the cell? 3. What occurs during cytokinesis? 1. The process of copying the cell s DNA; interphase 2. Metaphase 3. The cytoplasm divides, distributing the organelles between the two daughter cells.

23 Cell Biology 4 California Biology/Life Science Standard 8 6.b Oxygen Hydrogen Hydrogen Atoms and molecules are the basic building blocks of all cells. The most common elements in living things are carbon, oxygen, hydrogen, and nitrogen. Trace elements such as calcium, iron, potassium, phosphorus, sodium, and sulfur are also important. Water molecules are essential for most chemical reactions that take place within living cells. 1. Which two gases found in the atmosphere are needed by most living things? 2. What property of water molecules enables most chemicals important for life to dissolve in water? 1. Oxygen and carbon dioxide 2. They are polar.

24 Cell Biology 5 California Biology/Life Science Standard 8 6.c Cl Cl Na + Na + Water Water The body needs water because many of the body's processes, including chemical reactions, take place in water. Water is needed by plants for the process of photosynthesis. 1. How do solutions differ from other types of mixtures? 2. How does water s property as a solvent affect the composition of blood, which is mainly water? 1. Their components are evenly distributed. 2. Because it is mostly water, blood can transport dissolved molecules (such as glucose) and ions (such as sodium), which are essential for cells to perform their functions.

25 Cell Biology 6 California Biology/Life Science Standard BI 1.a Outside of Cell Cell Membrane Proteins Carbohydrate chains Inside of Cell (cytoplasm) Protein channel Lipid bilayer The cell membrane controls the internal environment of a cell. Materials can move through the membrane by diffusion, osmosis, or active transport. The composition of nearly all cell membranes is a double-layered sheet called a lipid bilayer. Molecules move by diffusion from an area of higher concentration to an area of lower concentration. Water moves in or out of a cell by osmosis based on concentration differences across a cell membrane. Active transport moves materials through a cell membrane against a concentration gradient. 1. What is the function of the cell membrane? 2. What other molecules are found in the cell membrane? 1. The cell membrane regulates what enters and leaves the cell and provides protection and support. 2. Proteins and carbohydrate chains

26 Cell Biology 7 California Biology/Life Science Standard BI 1.a DIFFUSION Osmosis is the diffusion of water through a selectively permeable membrane. Substances diffuse from an area of higher concentration to an area of lower concentration. Osmosis is one of several processes that allow cells to maintain homeostasis. 1. How does a cell keep from taking in excess water? 2. Why can some substances pass through a cell membrane and others cannot? 1. As water molecules enter the cell, the pressure against the cell wall increases. The increase in pressure then slows down the movement of water molecules into the cell. 2. Because a cell membrane is selectively permeable, meaning it allows only some substances to pass through it

27 Energy Molecule to be carried Cell Biology 8 California Biology/Life Science Standard BI 1.a Molecule being carried Cells must move waste products across the cell membrane to maintain homeostasis within the cell. Diffusion, osmosis, and active transport move materials across the cell membrane. Active transport moves materials against a concentration gradient and requires an input of energy from the cell. Question Name two differences between active transport and diffusion. Active transport requires energy input from the cell; diffusion does not require energy; diffusion moves materials from an area of greater concentration to an area of less concentration while active transport moves materials against a concentration gradient.

28 Cell Biology 9 California Biology/Life Science Standard BI 1.b Effect of ph on Catalase Activity 180 Pressure of Oxygen (kpa) Control Base added Acid added Time (seconds) Most cells function best within a narrow range of temperature and acidity. Extreme changes may harm cells because they change the structure of their proteins. Enzymes increase the rate of a reaction by reducing the activation energy needed to get the reaction started. Most enzymes are proteins. When conditions are too acidic or too alkaline, enzymes do not work as well and reactions are slower than when the ph is optimal. 1. What happens to the rate of the reaction in the presence of an acid? 2. What happens to the rate of the reaction when a base is added? 1. The reaction is inhibited in the presence of an acid. 2. The rate slows in the presence of a base.

29 Cell Biology 10 California Biology/Life Science Standard BI 1.b Enzyme (hexokinase) Glucose ADP Products Substrates Glucose phosphate ATP C Products are released Active site Enzyme - substrate complex A Substrates bind to enzyme B Substrates are converted into products Enzymes are biological catalysts. They speed up chemical reactions in cells. Substrates bind to the active site on an enzyme. The active site and the substrate have complementary shapes. They fit together like a lock and a key. When the reaction is complete, the products of the reaction are released and the enzyme is free to start the process again. 1. How do enzymes speed up chemical reactions? 2. Where on an enzyme does a reaction take place? 3. What would happen if a cell lacked a key enzyme? 1. They lower the activation energy needed for the reaction. 2. The active site 3. The reaction the cell catalyzes would take place too slowly and the cell might not survive.

30 Cell Biology 11 California Biology/Life Science Standard BI 1.c Cell membrane Prokaryotic Cell Cytoplasm Cell membrane Biologists divide cells into eukaryotes, which have a membrane-bound nucleus, and prokaryotes, which lack a membrane-bound nucleus. Prokaryotes are generally smaller and simpler than eukaryotes. Bacteria are prokaryotes. Cytoplasm Nucleus Eukaryotes contain dozens of specialized structures and membranes. Plants, animals, fungi, and protists are eukaryotes. Organelles 1. What invention allowed scientists to discover that living things are made from cells? Eukaryotic Cell 2. What other differences do you see between prokaryotic and eukaryotic cells? 1. The microscope 2. Eukaryotic cells contain organelles and are much larger than prokaryotic cells.

31 Cell Biology 12 California Biology/Life Science Standard BI 1.c Viruses and Cells Characteristic Virus Cell Structure DNA or RNA core, capsid Cell membrane, cytoplasm; eukaryotes also contain nucleus and organelles Reproduction Genetic Code Growth and Development Obtain and Use Energy Response to Environment Change Over Time only within a host cell DNA or RNA no no no yes independent cell division either asexually or sexually DNA yes; in multicellular organisms, cells increase in number and differentiate yes yes yes A virus has an outer coat of protein and an inner core containing either DNA or RNA. Viruses reproduce by invading a living cell and using the host cell s machinery to replicate. 1. How do viruses compare to cells in methods of reproduction? 2. What is one characteristic shared by viruses and cells? 1. Viruses must enter living cells and exploit host machinery to reproduce; whereas cells reproduce by cell division either asexually or sexually. 2. Sample answer: The fact that they change over time.

32 Cell Biology 13 California Biology/Life Science Standard BI 1.d RNA Adenine (DNA and RNA) Cytosine (DNA and RNA) Guanine (DNA and RNA) Thymine (DNA only) Uracil (RNA only) RNA polymerase DNA During transcription, RNA polymerase binds to DNA and separates the DNA strands. RNA polymerase then uses one strand of DNA as a template from which nucleotides are assembled into a strand of RNA. There are three main differences between RNA and DNA: the sugar in RNA is ribose instead of deoxyribose, RNA is generally single-stranded, and RNA contains uracil in place of thymine. 1. Where in the cell does transcription occur? 2. What RNA nucleotide sequence would be transcribed from the DNA sequence ACG? 1. In the nucleus 2. UGC

33 Cell Biology 14 California Biology/Life Science Standard BI 1.e Protein Amino acids Some of the proteins synthesized by the cell are used within the cell; others are exported from the cell. Proteins that are exported from the cell are synthesized on the rough endoplasmic reticulum. The Golgi apparatus modifies, sorts, and packages proteins and other materials for export from the cell. 1. Are proteins synthesized in the nucleus or in the cytoplasm of a cell? 2. What are the building blocks of proteins? 1. Cytoplasm 2. Amino acids

34 Cell Biology 15 California Biology/Life Science Standard BI 1.f Light H2O Light- Dependent Reactions NADP+ ADP + P ATP NADPH CO2 Calvin Cycle Chloroplast O2 Sugars During photosynthesis, plants and some other organisms use energy from the sun to convert carbon dioxide and water into oxygen and sugars, including glucose. The light-dependent reactions produce oxygen gas and convert ADP and NADP + into the energy carriers ATP and NADPH. The Calvin cycle uses ATP and NADPH to produce high-energy sugars. 1. What is the cycle that produces high-energy sugars during photosynthesis? 2. What are the products of the light-dependent reactions? 3. Where does photosynthesis take place? 1. The Calvin cycle 2. O 2, ATP, NADPH 3. chloroplasts

35 Cell Biology 16 California Biology/Life Science Standard BI 1.g Electrons carried in NADH Glucose Glycolysis Pyruvic acid Krebs Cycle Electrons carried in NADH and FADH 2 Electron Transport Chain Cytoplasm Mitochondrion ATP ATP ATP Living things get the energy they need from food. Cellular respiration is the process that releases energy by breaking down food molecules in the presence of oxygen. Mitochondria are organelles that convert the chemical energy stored in food into compounds that are easier for the cell to use. 1. What does glycolysis break down? 2. What takes place in the mitochondria? 1. Glucose 2. Krebs cycle and electron transport

36 Cell Biology 17 California Biology/Life Science Standard BI 1.h Starch Complex Carbohydrates Cellulose Glycerol Glucose Fatty acids Lipids The four basic types of organic molecules found in all cells are carbohydrates, lipids, proteins, and nucleic acids. Carbohydrates and lipids are used by living things for energy to fuel biological processes. Proteins and nucleic acids are used to build and repair body parts. Proteins Amino Acids Nucleotides Nucleic Acids 1. What are the monomers that make up each basic type of organic molecule? 2. What two forms of carbohydrates are made from long chains of glucose molecules connected in different arrangements? 3. What two important kinds of molecules in all cells are nucleic acids? 1. Carbohydrates glucose; lipids glycerol and fatty acids; proteins amino acids; nucleic acids nucleotides 2. Starch and cellulose 3. DNA and RNA

37 Cell Biology 18 California Biology/Life Science Standard *BI 1.i A Electron Transport B Hydrogen Ion Movement Channel H + H + Intermembrane Space H + H + H + H + H + ATP synthase Inner Membrane e - e - e - e - H O 2 2 H 2 O ADP H + ATP Matrix 2 NADH FADH 2 2 NAD + FAD C ATP Production Cell membranes contain a protein called ATP synthase that spans the membrane. As H + ions pass into the ATP synthase, it spins. Each time it rotates, the enzyme grabs a low-energy ADP and attaches a phosphate forming high-energy ATP. Question What is the role of ATP synthase during cellular respiration? To generate ATP

38 Cell Biology 19 California Biology/Life Science Standard *BI 1.j Cell membrane Endoplasmic reticulum Microtubule Microfilament Ribosomes Mitochondrion The cytoskeleton helps the cell maintain its shape. It also is involved in cell movement. The cytoskeleton is made up of microfilaments and microtubules. Microfilaments are made up of the protein actin. Microtubules are made up of proteins called tubulins. Microtubules form cilia and flagella. 1. What are two functions of the cytoskeleton? 2. How do organisms, such as paramecia, use cilia to move? 1. Maintenance of cell shape and support. 2. Paramecia move their cilia like tiny oars to move through liquids

39 Genetics 20 California Biology/Life Science Standard 7 2.a Unicellular organisms, many simple animals, and many plants reproduce asexually at least during one part of their life cycles. Asexual reproduction takes place by mitosis. Each offspring has the same genetic information as its parent. There are three types of asexual reproduction: binary fission, budding, and spore formation. In binary fission, the parent organism divides into two equal parts. In budding, the parent organism divides into two unequal parts. New organisms develop from the smaller outgrowth, or bud. Spores are specialized cells that germinate and form new organisms when released by the parent organism. 1. How is binary fission different from budding? 2. Does asexual reproduction increase genetic diversity? Explain. 1. Binary fission: parent divides into two equal parts; budding: parent divides into two unequal parts 2. No, because offspring are genetically identical to parent

40 Genetics 21 California Biology/Life Science Standard 7 2.a Haploid (N) Diploid (2N) Anther (2N) Pollen grains (N) (male gametophyte) Stigma Style MEIOSIS Pollen tubes Ovary Haploid cell (N) Ovule Embryo sac (N) (female gametophyte) Ovary (2N) Egg cell Mature sporophyte Sperm Pollen tube Polar nuclei Embryo (2N) Endosperm (3N) FERTILIZATION Seedling (2N) (new sporophyte) Endosperm Seed coat Fruit Zygote (2N) During sexual reproduction, cells from two different parents unite to form a new organism. In flowering plants, reproduction takes place within the flower. After pollination, the seeds develop inside protective structures. Pollination is the transfer of pollen from the male reproductive structure to the female reproductive structure. Most flowering plants are pollinated by animals, such as insects. 1. Does sexual reproduction increase genetic diversity? 2. How does the bright color of flowers help in pollination? 1. Yes, because offspring contain genes from two parents. 2. Bright colors attract insects.

41 Genetics 22 California Biology/Life Science Standard 7 2.c RR R R W RW RW WW W RW RW Some alleles are neither dominant nor recessive. The pink flowers (in the example) are a result of incomplete dominance. In incomplete dominance, neither the red flower gene nor the white flower gene is dominant. Sometimes both alleles contribute to the phenotype. This is called codominance. Chickens with both black and white feathers show codominance (both the black and white feathers are dominant). When genes have two or more alleles, they are said to have multiple alleles. Human blood type is an example of a trait controlled by multiple alleles. Traits that are controlled by two or more genes are polygenic traits. Polygenic traits, such as human skin color, show a wide variety of phenotypes. Question What is the difference between incomplete dominance and codominance? In incomplete dominance, neither gene is dominant; in codominance, both genes are dominant.

42 Genetics 23 California Biology/Life Science Standard 7 2.d In the mid-nineteenth century, Gregor Mendel experimented with thousands of pea plants to understand the process of heredity. A trait is a specific characteristic, such as seed color or stem height, that varies from one individual to another. Mendel learned that an organism s inherited traits are determined by the alleles it receives from its parents. Alleles are different forms of a gene and can be dominant or recessive. 1. List 5 examples of inherited traits. 2. Are blue eyes as a result of contact lenses an example of an inherited trait? Explain. 1. Examples may include any of the traits listed above, or human examples such as eye color, skin color, height, and presence of dimples. 2. No; eye color as a result of contact lenses is not genetically inherited. The person s natural eye color would be an inherited trait.

43 Genetics 24 California Biology/Life Science Standard 7 2.e T A A C T G C G Chromosome DNA molecule Nitrogen bases DNA is organized into chromosomes, which are found within the nuclei of cells. A gene is a segment of DNA on a chromosome that codes for a specific protein and thus determines a trait. The genetic code is determined by the order of bases in the gene, which specifies what type of protein will be produced. 1. Why is DNA wrapped so tightly in chromosomes? 2. How are DNA, proteins, and traits related? 1. In order to fit into the nucleus 2. DNA codes for proteins; proteins determine traits.

44 Genetics 25 California Biology/Life Science Standard BI 2.a 1 Beginning of Meiosis 2 Meiosis I Most multicellular organisms reproduce sexually. Sexual reproduction involves the fusion of two sex cells, each of which carries half the number of chromosomes as the body cells. Meiosis is the process by which the number of chromosomes is cut in half to produce sex cells. Cells undergo two divisions after one replication of the DNA. This results in four sex cells, each with half the original number of chromosomes. 3 Meiosis II 4 End of Meiosis 1. What types of cells are formed by meiosis? 2. Since a human body cell has 46 chromosomes, how many chromosomes does a human sex cell contain? 3. When a human egg and sperm combine, how many chromosomes are in each body cell of the offspring? 1. Sex cells, or sperm and eggs

45 Genetics 26 California Biology/Life Science Standard BI 2.b In Males 2N N N Meiosis I Meiosis II Meiosis is how sexually reproducing organisms produce gametes. Sperm N N N N In male animals, the haploid gametes are called sperm. In female animals, the haploid gamete is called an egg. In females, usually only one of the cells produced by meiosis is involved in reproduction. In Females N 2N N N Meiosis I N N N Meiosis II 1. In general, what is the end result of meiosis? 2. What is the end result of meiosis in female animals? Polar bodies Egg 1. Four haploid cells 2. One large egg and three smaller polar bodies

46 Genetics 27 California Biology/Life Science Standard BI 2.c Crossing-Over A B C D E A B C D E A B C D E A B C D E A BC e A B c d e c d b a D E a b c d e a b C D E a b c d e a b c d e a b c d e Sorting and recombination of genes during sexual reproduction results in a great variety of possible gene combinations from the offspring of any two parents. Most genetic variation is due to the gene shuffling that occurs during the production of gametes. Genetic variation can also result from such processes as crossing over, jumping genes, and deletion and duplication of genes. 1. What process is shown in the figure? 2. During which phase of meiosis does crossing over occur? 3. What is the result of crossing over? 1. Crossing over 2. Prophase I 3. The exchange of alleles between homologous chromosomes and thus new combinations of alleles

47 Genetics 28 California Biology/Life Science Standard BI 2.d Zygote 2 cells 4 cells Morula Blastocyst Fallopian tube Fertilization Sperm cells Day 0 Ovary Uterine wall Day 7 Blastocyst implants into uterine wall Ovulation When a haploid sperm joins a haploid egg, fertilization takes place. A fertilized egg (zygote) contains the combined genotypes of both parents and produces new allele combinations for the offspring. Punnett squares can be used to show the possible combinations of alleles. 1. Will the offspring ever have an identical genetic makeup to either of its parents? 2. Is the zygote formed during fertilization haploid or diploid? 1. No, because of the random allele combinations. 2. diploid

48 Genetics 29 California Biology/Life Science Standard BI 2.e Each parent contributes to each offspring one allele out of a possible two for each trait. A Punnett square shows all possible outcomes of a genetic cross and the probability of each occurring. Four possible combinations of alleles can result for one trait. The probability of an offspring receiving each combination can be predicted. 1. Why is it necessary to know the genotype of each parent to create a Punnett square? 2. When two pea plants that are heterozygous for height are crossed, what percentage of the offspring will be heterozygous? Will be tall? 3. The Punnett square models the segregation of alleles. During which process are alleles separated? 1. You need to know which alleles each parent could possibly contribute to the offspring out of 4, or 50%; 3 out of 4, or 75% 3. Gamete formation or meiosis

49 Genetics 30 California Biology/Life Science Standard BI 2.f Organisms are characterized by a specific number of chromosomes. Human body cells contain 23 pairs of chromosomes. One pair of human chromosomes, known as sex chromosomes, determines gender. Females have two X chromosomes and males have an X and a Y chromosome. 1. What are male and female sex cells called? 2. How many chromosomes are contained within each sex cell? 3. According to the Punnett square, what is the likelihood that a human baby will be a boy? 1. sperm and egg cells %

50 Genetics 31 California Biology/Life Science Standard BI 2.g In the example shown, two pea plants are crossed. The types of gametes produced by each parent are shown along the top and left sides of the Punnett square. The possible gene combinations for the offspring appear in the four boxes in the square. T represents the dominant allele for tallness and t represents the recessive allele for shortness. 1. Are any of the offspring homozygous? Which ones? 2. Which genotype(s) represents tall plants? 3. Which genotype(s) represents short plants? 1. Yes, TT and tt 2. TT, Tt 3. tt

51 Genetics 32 California Biology/Life Science Standard BI 3.a The results of a genetic cross can be predicted using the principles of probability. Geneticists use Punnett squares to show all possible outcomes of a genetic cross and to determine the probability of each outcome. To use a Punnett square, you must know the genotype of each parent. Each parent contributes one of two alleles for each trait to each offspring. 1. Why is it necessary to know the genotype of each parent to create a Punnett square? 2. When two pea plants that are heterozygous for height are crossed, what percentage of the offspring will also have the heterozygous genotype? What percentage will be tall? 1. You need to know which alleles each parent could possibly contribute to the offspring. 2. Two out of four, or 50% will be heterozygous; three out of four, or 75% will be tall.

52 Genetics 33 California Biology/Life Science Standard BI 3.a Some Autosomal Disorders in Humans Type of Disorder Disorders caused by recessive alleles Disorders caused by dominant alleles Disorders caused by codominant alleles Disorder Albinism Cystic fibrosis Galactosemia Phenylketonuria (PKU) Tay-Sachs disease Achondroplasia Huntington s disease Hypercholesterolemia Sickle cell disease Major Symptoms Lack of pigment in skin, hair, and eyes Excess mucus in lungs, digestive tract, liver; increased susceptibility to infections Accumulation of galactose (a sugar) in tissues; mental retardation; eye and liver damage Accumulation of phenylalanine in tissues; lack of normal skin pigment; mental retardation Lipid accumulation in brain cells; mental deficiency; blindness; death in early childhood Dwarfism (one form) Mental deterioration and uncontrollable movements; symptoms usually appear in middle age Excess cholesterol in blood; heart disease Misshapen, or sickled, red blood cells; damage to many tissues Mendel s principle of dominance states that some alleles are dominant and others are recessive. An organism with a dominant allele will always exhibit that form of the trait. An organism with a recessive allele will exhibit that form only when the dominant allele for the trait is not visible. 1. What disorders are caused by recessive alleles? 2. If a person inherits one dominant and one recessive allele for Huntington disease, would he or she develop Huntington disease? Explain. 1. Albinism, cystic fibrosis, galactosemia, PKU, Tay-Sachs 2. Yes, because the dominant allele always expresses itself if it is present.

53 Genetics 34 California Biology/Life Science Standard BI 3.a Genes control an organism s traits. Genes have alleles, which may be dominant or recessive. During sexual reproduction, offspring receive one allele from each parent. If the alleles are the same, the offspring has a homozygous genotype. If they are different, it has a heterozygous genotype. The phenotype, or the visible traits of an individual, depends on its genotype and the inheritance pattern of the alleles that control each trait. 1. How many alleles control each of the traits that Gregor Mendel studied in his pea plants? 2. Is the wrinkled seed shape controlled by a dominant allele or a recessive allele? 3. What is the genotype of a pea plant that has one green pod allele and one yellow pod allele? 1. Two 2. Recessive 3. Green pods

54 Genetics 35 California Biology/Life Science Standard BI 3.b P Generation F 1 Generation F 2 Generation X X Tall Short Tall Tall Tall Tall Tall Short The P generation represents the original pair of parents. The F 1 generation represents the first offspring (first generation) The F 2 generation represents the second generation. In the example illustrated, Mendel allowed the F 1 generation to self-pollinate to produce the F 2 generation. 1. If T = tall, and t = short, what is the genotype of the two P generation plants? 2. What is the genotype of the two F 1 generation plants? 3. What is the genotype of the four F 2 generation plants? 1. TT and tt 2. Both are Tt 3. TT, Tt, Tt, and tt

55 Genetics 36 California Biology/Life Science Standard *BI 3.c A circle represents a female. A square represents a male. A horizontal line connecting a male and a female represents a marriage. A vertical line and a bracket connect the parents to their children. A shaded circle or square indicates that a person expresses the trait. A circle or square that is not shaded indicates that a person does not express the trait. Most human traits show many phenotypes because they are controlled by many genes, and some genes have multiple alleles. Genetic disorders, such as Down syndrome and cystic fibrosis, can be caused by mutations or by having too many or too few chromosomes. Pedigrees can be used to trace the inheritance of a trait in a family and to predict the probability that a child will be born with a genetic disorder. 1. How could a sex cell end up with too many chromosomes, such as in Down syndrome? 2. Is the trait traced by the pedigree autosomal or sex-linked? Is it dominant or recessive? 3. What is the probability that a child of the couple on the left above will be a female who has this trait? 1. During meiosis, chromosomes fail to separate properly, leaving two copies of a chromosome instead of one. 2. Autosomal; dominant 3. 50%

56 Genetics 37 California Biology/Life Science Standard *BI 3.d Exact location on chromosome Chromosome Aristaless (no bristles on antenna) Star eye 13.0 Dumpy wing Dachs (short legs) Black body 51.0 Reduced bristles Purple eye 55.0 Light eye Vestigial (small) wing 75.5 Curved wing Arc (bent wings) Brown eye Speck wing Genes located on the same chromosome are always inherited together and only rarely become separated from each other. Gene maps are used to show the relative locations of each known gene. 1. Where on the chromosome is the curved wing gene located? 2. Where on the chromosome is the black body gene located? 3. How far apart (on the gene) are the chromosomes for speck wing and vestigial (small) wing?

57 Genetics 38 California Biology/Life Science Standard BI 4.a RNA Adenine (DNA and RNA) Cytosine (DNA and RNA) Guanine (DNA and RNA) Thymine (DNA only) Uracil (RNA only) RNA polymerase DNA The first step in protein synthesis is to copy the DNA code into a molecule of RNA. During transcription, RNA polymerase binds to DNA and separates the DNA strands. RNA polymerase then uses one strand of DNA as a template from which nucleotides are assembled into a strand of RNA. 1. Where does transcription occur? 2. What binds with adenine during transcription? 1. in the nucleus 2. uracil

58 Amino acids trna Genetics 39 California Biology/Life Science Standard BI 4.a U A C A A G A U G U U C U U U A A A The cell uses information from mrna to make proteins. mrna Ribosome Translation direction Translation begins when a mrna molecule attaches to a ribosome. Polypeptide (growing protein chain) Ribosome Each ribosome moves along a mrna sequence, binding new trna molecules and joining amino acids into a protein. trna 1. Where does translation occur? 2. How many amino acids does a trna molecule carry? G A C C U G U G A 3. What property of trna allows it to recognize a particular codon on the mrna? mrna 1. Translation occurs at ribosomes in the cytoplasm. 2. One 3. Its anticodon sequence, which is complementary to a particular codon sequence on the mrna

59 Genetics 40 California Biology/Life Science Standard BI 4.b Valine Arginine Serine Alanine Lysine Aspartic acid C A G U C U A G AG U A G C C A U G G U U A C C C A U G C A G U A C C U G U G A U G G U A G U C C A U A C G G A C U A C C A U C A G G U G U A C C U A G G A C C U U G A Asparagine Glutamic acid Threonine Methionine Glycine Isoleucine Phenylalanine Arginine Leucine Glutamine Serine Histidine Tyrosine Proline Stop Cysteine Stop Tryptophan Leucine DNA sequences that code for proteins are called exons. Codons are three consecutive nucleotides that specify a single amino acid that is to be added to the polypeptide. A start codon signals the beginning of the codons to be translated. A stop codon ends the sequence to be translated into protein. 1. What is the genetic code? 2. What is a codon? 3. Which proteins do these codons represent: GGG AAA CCC? 1. The language of mrna instructions 2. Three consecutive nucleotides that specify a single amino acid 3. Glycine, Lysine, Proline

60 Genetics 41 California Biology/Life Science Standard BI 4.c THE THREE TYPES OF POINT MUTATIONS DNA: TAC GCA TGG AAT DNA: TAC GCA TGG AAT mrna: AUG CGU ACC UUA mrna: AUG CGU ACC UUA Amino acids: Met Arg Thr Leu Amino acids: Met Arg Thr Leu DNA: Substitution TAC GTA TGG AAT DNA: Insertion TAT CGC ATG GAA T THE FAT CAT ATE THE RAT mrna: AUG CAU ACC UUA mrna: AUA GCG UAC CUU A Deletion Amino acids: Met His Thr Leu Amino acids: Ile Ala Tyr Leu THE F AT C AT A TE T HE R AT TEF ATC ATA TET HER AT Mutations that produce changes in a single gene are called gene mutations. The majority of mutations are point mutations that affect just one nucleotide in the DNA sequence. Point mutations include substitutions, insertions, and deletions. 1. Which is a more serious point mutation, a substitution or an insertion? 2. When do substitutions have no effect on the protein product? 3. What causes mutations? 1. An insertion 2. When the new amino acid is the same as the one originally coded for 3. Radiation, chemicals, and so on

61 Genetics 42 California Biology/Life Science Standard BI 4.c A B C D E F Chromosomal mutations involve changes in the number or structure of chromosomes. Original chromosome A C D E F Deletion A B B C D E F Duplication The types of chromosomal mutations are deletion, duplication, inversion, and translocation. 1. What type of mutation occurs when one part of a chromosome breaks off and attaches to another? A E D C B F Inversion 2. What type of mutation involves the loss of part of a chromosome? A B C J K L G H I D E F 3. What type of mutation results in the reversal of the direction of part of the chromosome? Translocation 1. translocation 2. deletion 3. inversion

62 Genetics 43 California Biology/Life Science Standard BI 4.c Chromosome #7 Ile Ile Phe Gly CFTR gene Val Changes in DNA are harmful if they reduce an organism s chance to survive and reproduce. Cystic fibrosis (CF) is usually caused by the deletion of three bases in the gene that codes for a critical ion transport protein. When cells in the airways cannot transport chloride ions, thick mucus clogs the airways, leading to serious respiratory problems. 1. How many amino acids are missing in CF? 2. When can small changes in a DNA sequence have profound effects on a phenotype? 3. How might respiratory problems affect a person? 1. One 2. When the protein affected is a key protein needed to 3. By affecting the ability to breathe perform basic metabolic processes and perform normal activities

63 Genetics 44 California Biology/Life Science Standard BI 4.d Fruit fly chromosome Fruit fly embryo Mouse chromosomes Mouse embryo The cells in a multicellular organism are all descended from a single cell and have essentially identical genetic instructions. The cells in a multicellular organism can develop in different ways and carry out different tasks. This is called cell specialization. Different parts of a cell s genetic instructions are used in different types of cells and are influenced by the cell s environment and gene expression. This process is called cell differentiation. Hox genes control the differentiation of cells and tissues in the embryo. Adult fruit fly Adult mouse Question In the diagram, what section of the bodies of flies and mice is coded by the genes shown in purple? The very front end.

64 Genetics 45 California Biology/Life Science Standard BI 4.e H H O Amino Acids H H O N C C N C C N C C H OH H H R OH Amino Carboxyl H C H H C H group group H OH General structure Alanine Serine H H O OH Proteins are polymers of amino acids. The body is able to synthesize only 12 out of 20 amino acids used to make proteins. The other eight must come from food. The order in which amino acids are linked together to form proteins is controlled by genes. All amino acids have an amino group on one end and a carboxyl group on the other. The portion of each amino acid that is different is a side chain called an R-group. Some R-groups are acidic and some are basic. Some are polar and some are nonpolar. Question What is the general structure of an amino acid? Amino acids have an amino group at one end, a carboxyl group at the other end, hydrogen, and an R-group.

65 Genetics 46 California Biology/Life Science Standard *BI 4.f Protein Amino acids Proteins can have up to four levels of organization. The first level is the sequence of amino acids in a protein chain. Second, the amino acids within a chain can be twisted or folded. Third, the chain itself is folded. If a protein has more than one chain, each chain has a specific arrangement in space. Van der Waals forces and hydrogen bonds help maintain a protein's share. Question What is a protein? A polymer of amino acids.

66 Genetics 47 California Biology/Life Science Standard BI 5.a Purines Pyrimidines Adenine Guanine Cytosine Thymine Phosphate group Deoxyribose DNA is made up of a series of monomers called nucleotides. Each nucleotide has three parts: a deoxyribose molecule, a phosphate group, and a nitrogenous base. The purines have two rings in their structure, the pyrimidines have one ring. The backbone of the DNA chain is formed by sugar and phosphate groups of each nucleotide. 1. What two parts are the same in all nucleotides? 2. Which two nucleotides are purines? 1. The deoxyribose molecule and the phosphate group 2. Adenine and guanine

67 Genetics 48 California Biology/Life Science Standard BI 5.a Hydrogen bonds Key Adenine (A) Thymine (T) Cytosine (C) Guanine (G) A G T C C A G A Nucleotide G C T Sugar-phosphate backbone DNA is composed of two long chains of nucleotides, joined together in a double helix. The four nitrogenous bases in DNA are adenine, guanine, cytosine, and thymine. Hydrogen bonds form between certain nitrogenous bases to hold the two strands together. 1. How is the double helix held together? 2. Why are there equal amounts of adenine and thymine, and guanine and cytosine in DNA? 3. How is base pairing between adenine and thymine different from pairing between guanine and cytosine? 1. By hydrogen bonds 2. A always pairs with T; G always pairs with C. 3. There are two hydrogen bonds between A and T; three between G and C.

68 Genetics 49 California Biology/Life Science Standard BI 5.a Ribosome Amino acid Uracil Messenger RNA Ribosomal RNA Transfer RNA Messenger RNA (mrna) molecules carry the instructions for assembling amino acids into proteins from DNA to the rest of the cell. Various proteins as well as ribosomal RNA (rrna) make up ribosomes. Transfer RNA (trna) molecules transfer each amino acid to the ribosome as it is specified by coded messages in mrna. 1. What are ribosomes made of? 2. What is the main function of RNA? 1. proteins and rrna 2. to make proteins

69 Nitrogenous bases Genetics 50 California Biology/Life Science Standard BI 5.b Original strand New strand Growth Growth DNA polymerase Replication fork DNA polymerase Original strand New strand In most prokaryotes, DNA replication begins at a single point on the chromosome. In eukaryotes, DNA replication begins at several places. In replication, DNA unwinds into two strands, which act as templates for complementary strands. New bases are added following the rules of base pairing. 1. Are there more replication forks in prokaryote or eukaryote DNA during replication? KEY Adenine (A) Thymine (T) Cytosine (C) Guanine (G) Replication fork 2. If a strand of DNA has the bases TATACCG, what are the complementary bases? 1. More in eukaryote DNA 2. ATATGGC

70 Nitrogenous bases Genetics 51 California Biology/Life Science Standard BI 5.b Original strand New strand Growth Growth Replication fork DNA polymerase Original strand New strand DNA polymerase unzips the molecule of DNA. The bonds between the base pairs are broken and the two strands unwind. Each DNA molecule resulting from replication has one original strand and one new strand. DNA polymerase 1. Which bonds are broken during replication? 2. How many DNA molecules in total would there be after four DNA molecules replicate? KEY Adenine (A) Thymine (T) Cytosine (C) Guanine (G) Replication fork 1. The hydrogen bonds between the bases 2. Eight molecules total

71 Genetics 52 California Biology/Life Science Standard BI 5.c Agrobacterium tumefaciens Gene to be transferred Cellular DNA Recombinant plasmid Inside plant cell, Agrobacterium inserts part of its DNA into host cell chromosome. Plant cell colonies Transformed bacteria introduce plasmids into plant cells. Complete plant is generated from transformed cell. Genetic engineering can be used to help in medicine and agriculture. First, the DNA must be cut into small pieces that contain a certain gene. Second, the different pieces of DNA must be inserted into another species (usually a bacterium). Third, the organisms with the foreign DNA must be cloned. If the transformation is successful, the new recombinant DNA is integrated into the chromosomes of the cell. How could farmers make use of genetic engineering to improve their crops? They could develop genes that increase plants resistance to pests or viruses.

72 Genetics 53 California Biology/Life Science Standard 8BI 5.d DNA plus restriction enzyme Power source Longer fragments Shorter fragments Mixture of DNA fragments Gel In order to analyze DNA, biologists cut the DNA molecules into smaller fragments using restriction enzymes. Restriction enzymes will cut a DNA sequence only if it matches the sequence precisely. Gel electrophoresis can then be used to separate and analyze the DNA fragments. Question Why might scientists want to analyze genomes? To locate a specific gene, to compare genes from different organisms.

73 Genetics 54 California Biology/Life Science Standard *BI 5.e 1 Plasmids removed from bacteria Genetic engineering is a process by which genes from one organism are transferred into the DNA of another organism. 3 4 Plasmid DNA and human insulin gene spliced together New plasmids taken up by bacteria 2 Enzymes remove human insulin gene from its chromosome and cut open plasmid DNA Scientists use genetic engineering to produce bacterial and animal cells that produce human proteins, such as insulin, for medical treatments. Genetic engineering has been used to insert bacterial genes into crops to make more useful varieties. 5 New generation of bacteria contains copies of engineered plasmid 1. Why are bacteria a good choice for insertion and production of the human insulin gene? 2. What are the advantages of using human insulin created by genetic engineering instead of animal insulin from the pancreas of a sheep or pig? 1. They can be grown easily and quickly to produce large amounts of insulin. 2. It works better and is less likely to produce an allergic reaction.

74 Ecology 55 California Biology/Life Science Standard 6 5.b Zooplankton Small fish Algae Squid Shark Energy flows through an ecosystem in one direction, from the sun or inorganic compounds to autotrophs (producers) and then to various heterotrophs (consumers). Food chains show the one-way flow of energy in an ecosystem. 1. Which organism in the food chain above is an autotroph? 2. For what do heterotrophs depend on autotrophs? 1. Algae 2. Energy/food supply

75 Ecology 56 California Biology/Life Science Standard 6 5.b Fox Hawk Snake Energy flows through an ecosystem in one direction, from producers to consumers. The network of feeding relationships within an ecosystem is represented by a food web. Bird Each step in a food chain is a trophic level. Each consumer derives energy from the level before it. Rabbit Owl Mouse Frog Grasshopper Grasses 1. How many consumers derive their energy from grasses in this food web? 2. Which organism derives its energy from the most number of sources? 3. What effect do you think a drought would have on a prairie food web? 1. Three 2. The hawk 3. The primary consumers and all the levels above them would not get enough food and energy.

76 Ecology 57 California Biology/Life Science Standard 6 5.c The sun is the source of energy for most living things. Plants such as grass use energy from the sun to make their own food. The zebra obtains energy by eating grass. The lion obtains energy by feeding on the zebra. The sun directly or indirectly supplies the energy used by all living things. Producers, such as plants, convert radiant energy from the sun into chemical energy (sugars). Consumers, such as animals, get energy by eating food (plants or other animals). About 60% of all food energy taken in by organisms is lost to the environment as heat. 1. What is the ultimate source of energy for all living things? 2. Compare the way plants and animals get energy. 3. How have humans had a negative effect on ecosystems? 1. The sun 2. Plants convert energy from the sun into sugars; animals eat food. 3. By polluting the air and water and by destroying habitats.

77 Ecology 58 California Biology/Life Science Standard 6 5.c LICHEN Densely packed hyphae Layer of algae or cyanobacteria Loosely packed hyphae Densely packed hyphae In commensalism, one organism benefits and the other is neither helped nor harmed. In a mutualistic relationship, both species benefit from the relationship. Lichen is composed of fungus and a photosynthetic organism (an alga or a cyanobacterium) in a mutualistic relationship. 1. Would fungus alone be able to survive on bare rock? Why or why not? 2. What part of the lichen shields the algae or cyanobacteria from the environment? 1. No. It would not have an energy source. 2. The upper layer of densely packed hyphae

78 Ecology 59 California Biology/Life Science Standard 6 5.e 60 N Tropical rain forest Tropical dry forest 30 N Tropical savanna Temperate grassland Equator 30 S 60 S Miles Kilometers Desert Temperate woodland and shrubland Temperate forest Northwestern coniferous forest Boreal forest (Taiga) Tundra Mountains and ice caps Biotic factors are biological influences on organisms within an ecosystem. Physical, or nonliving, factors that shape ecosystems are called abiotic factors. In tropical biomes, abiotic factors include warm temperatures and rainfall that ranges from high in rain forests to low in deserts. In temperate biomes, temperatures are generally hot to mild in summer and cold in winter. Precipitation is usually moderate. 1. What abiotic factors might be important to organisms living on the floor of a tropical rain forest? 2. What biotic factors might be important to insects living on the floor of a tropical rain forest? 3. What major abiotic factor besides latitude can affect the temperature and precipitation of an area? 1. Warm temperatures, high precipitation, high humidity, low sunlight, and so on 2. Fungi, plants, bacteria, and other animals living on the rain forest floor 3. Elevation

79 Ecology 60 California Biology/Life Science Standard BI 6.a! " Ecosystems are constantly changing in response to natural and human disturbances. A series of predictable changes that occur in a community over time is called ecological succession. Succession that occurs where no soil exists is called primary succession. If a disaster, such as flood or fire occurs, the damaged ecosystem is likely to recover in stages that eventually result in a system similar to the original one. This is called secondary succession. 1. What kind of succession is shown in the diagram? 2. What pioneer species are shown in stage 2 in the diagram? 3. What are some other natural and human activities that might cause secondary succession? 1. Primary succession 2. Lichens 3. Answers include volcanoes and tornadoes (natural) and cutting down trees or mining areas (human).

80 Ecology 61 California Biology/Life Science Standard BI 6.b N Miles Kilometers W S E States with zebra mussel populations Zebra mussels are not native to the United States. They were introduced to the U.S. from Eastern Europe and Asia by ships from these areas. Zebra mussels have caused serious structural damage and clogged water supply lines. In some habitats, zebra mussels have displaced native mollusk species, making them almost extinct. They have also depleted the food supplies of many fish species. 1. According to the map, which state appears to have the most widespread zebra mussel problem? 2. Read page 700 in your textbook. Do you think zebra mussels will spread to other states? Why or why not? 3. What do you think should be done about zebra mussels? Use library and other sources to support your answer. 1. Michigan 2. Answers should clarify and defend a position with precise and relevant evidence. 3. Students should consult appropriate sources and write an analytical essay. Essays should include precise and relevant evidence.

81 Ecology 62 California Biology/Life Science Standard BI 6.c Major interactions among organisms are competition, predation, and symbiosis. MOOSE AND WOLF POPULATIONS ON ISLE ROYALE Wolves Moose Interactions between organisms help shape the environment. The population of wolves, which feed on moose, fluctuates with moose numbers. 1. Which type of interaction occurs between wolves and moose? Year 2. Relative to the wolf population, when does the moose population increase in size? 3. What would you expect to see during a year when moose can t find enough to eat? 1. Predation 2. When the wolf population decreases 3. Lower moose numbers, which in turn lowers wolf numbers

82 Ecology 63 California Biology/Life Science Standard BI 6.c Human Population Growth Billions of People Agriculture begins Plowing and irrigation Bubonic plague Industrial Revolution begins ,000 BC 9000 BC 8000 BC 7000 BC 6000 BC 5000 BC 4000 BC Year 3000 BC 2000 BC 1000 BC AD AD As resources become less available, the growth of a population slows or stops. Logistic growth occurs when a population s growth slows or stops following a period of exponential growth. The largest number of individuals that a given environment can support is called the carrying capacity of the environment for a particular species. This occurs when the average growth rate is zero. 1. According to the graph, when did the human population begin growing rapidly? 2. What are some factors that limited the size of the human population of the past? 3. What kind of growth does the graph show? 1. About 500 years ago 2. Scarce food, disease 3. Exponential growth

83 Ecology 64 California Biology/Life Science Standard BI 6.d Ocean Water vapor EVAPORATION Lake CONDENSATION PRECIPITATION Groundwater The water cycle begins when water evaporates from oceans, lakes, and rivers, and is released from plants or animals. Water vapor condenses as it cools to form clouds. When the water droplets become heavy enough, they fall back to Earth as precipitation. Precipitation that falls on land can evaporate, flow into rivers and lakes, or seep into the ground where it will flow into lakes and oceans. RUNOFF AND GROUNDWATER 1. What source of energy drives the water cycle? 2. How does the water cycle renew Earth s supply of fresh water? 3. What happens to rain that falls into the oceans? 1. The sun 2. Most of the water that evaporates comes from the salty oceans but becomes fresh as it evaporates. 3. It remains in the ocean until it evaporates and continues the cycle.

84 Ecology 65 California Biology/Life Science Standard BI 6.e Plant produces oxygen Plant Plant uses carbon to make sugar molecules Animal takes in oxygen carbon dioxide takes in Animal carbon releases dioxide Animal breaks down sugar molecules The amount of life any environment can support is limited by the available energy, water, oxygen, and minerals, and by the ability of ecosystems to recycle materials. Matter, such as water, nutrients, and minerals, recycles within and between ecosystems. Carbon is the building block of all organic matter. It is present in carbon dioxide in the atmosphere, and is used by plants to produce carbohydrates. 1. How does the horse obtain energy by eating apples? 2. In the carbon cycle, how do animals benefit plants? 3. What is one major effect of deforestation on the atmosphere? 1. By breaking down sugar molecules 2. Animals produce carbon dioxide that plants need. 3. Less carbon dioxide is absorbed. Increased levels of CO 2 in the atmosphere contribute to global warming.

85 Ecology 66 California Biology/Life Science Standard BI 6.f Light or chemical energy 0.1% Third-level consumers 1% Second-level consumers 10% First-level consumers Ecological pyramids show the relative amounts of energy or matter available within each trophic level in a food chain or food web. Most energy is contained at the producer level. Only about 10 percent of the energy available in each level is transferred to the level above it. H E A T 100% Producers 1. Which trophic level harnesses energy from the sun or from chemicals? 2. What happens to the rest of the energy that isn t passed on to the next trophic level? 3. How would consumers benefit by being part of a shorter food chain? 1. The first trophic level (producers) 2. It is lost to the environment as heat. 3. They would be harvesting more of the energy initially available.

86 Ecology 67 California Biology/Life Science Standard *BI 6.g Nine-Banded Armadillo PACIFIC OCEAN NORTH AMERICA ATLANTIC OCEAN SOUTH AMERICA EUROPE AFRICA ASIA INDIAN OCEAN PACIFIC OCEAN AUSTRALIA Chinese Pangolin Common Echidna ANTARCTICA Giant Anteater Aardvark Living organisms adapt to changing environments through changes in structure or behavior. This trend has occurred many times throughout life s history and contributes to the diversity of plants and animals. Unrelated mammal species that feed on ants and termites developed in five different regions. 1. What features help these ant- and termite-eating mammals find and dig out insects? 2. How are the armadillo and pangolin adapted to fending off predators? 3. What can you infer about the environments where these five different mammals are found? 1. Claws, long snout, and long sticky tongue 2. They have hard scaly armor. 3. They present similar ecological opportunities.

87 Evolution 68 California Biology/Life Science Standard 7 3.a Evolution is any change in time in the relative frequencies of alleles in a population. Evolution studies the varieties and interactions of living things across time. A great diversity of species increases the chance that at least some living things will survive in the face of large changes in the environment. 1. What is a population? 2. Suggest a reason why the population of brown lizards decreased. 1. A group of individuals that belong to the same species and live in the same area. 2. Answers will vary. Students may suggest that environmental factors caused more brown lizards to be eaten.

88 Evolution 69 California Biology/Life Science Standard 7 3.b Pinta Island Intermediate shell Marchena Pinta Tower James Fernandina Isabela Santa Fe Santa Cruz Floreana Hood Hood Island Saddle-backed shell Isabela Island Dome-shaped shell During his travels, Darwin made numerous observations and collected evidence that led him to propose his theory of evolution. Geologists James Hutton and Charles Lyell helped scientists recognize that the Earth was very old and that the processes that changed Earth in the past were the same processes that operate today. 1. What are some ways Earth has changed over time? 2. How did Hutton and Lyell influence Darwin s thinking? 1. Students may suggest that mountains have been built up, or earthquakes have buried other rock 2. Darwin thought that if Earth could change, life could change as well.

89 Evolution 70 California Biology/Life Science Standard 7 3.c Turtle Alligator Bird Mammals Typical primitive fish Homologous structures provide evidence that all four-limbed vertebrates share a common ancestor. Limbs of different vertebrates have different functions but are structurally similar and develop from the same embryonic tissues. Fossils of ancient whale-like animals with legs suggest that whales and other mammals likely share a common ancestor. 1. How are the bones similar across the four groups? 2. Would lighter bones be more advantageous for an animal that lived in the air or on land? 1. Similar arrangement and number 3. In air. (Lighter bones are easier to lift, such as in flight; heavier bones offer more structural support, as needed to bear weight on the ground.)

90 Cell Biology 71 California Biology/Life Science Standard BI 1.a The phenotype of an organism is its physical characteristics. The genotype of an organism is its genetic makeup. Natural selection works on the phenotype of an organism. 1. Why might the red lizard population have disappeared? 2. Which lizard population brown or black is more successful in this example? 1. They may have been more visible to predators 2. black

91 Evolution 72 California Biology/Life Science Standard BI 7.b Organisms that have two identical alleles for a particular trait are homozygous. Organisms that have two different alleles for the same trait are heterozygous. A genetic disorder caused by a recessive allele, such as Tay-Sachs disease, only appears if the individual inherits two recessive alleles for the trait. A heterozygous individual still contributes the allele to the gene pool even if the person doesn t have the disorder. Question Both parents are heterozygous for Tay-Sachs disease. What is the chance that their offspring will have Tay-Sachs? (Hint: Use a Punnett square for help.) 1 in 4 chance.

92 Evolution 73 California Biology/Life Science Standard BI 7.c The two main sources of genetic variation are mutations and the genetic shuffling that results from sexual reproduction. Plant breeders use several methods to increase genetic variation in plants and to produce new types of plants. A mutation is any change in the sequences of DNA. Some mutations affect an organism s phenotype, while others do not. 1. Describe one way in which natural selection could act on a plant characteristic. 2. Name one characteristic that plant breeders might select for. 1. Sample answer: If average temperatures in an area increase over time, plants with greater heat tolerance will be more likely to survive and reproduce. 2. Sample answer: Resistance to pests

93 Evolution 74 California Biology/Life Science Standard BI 7.d Sample Population The number of phenotypes a given trait has is determined by how many genes control the trait. 48% heterozygous black 36% homozygous brown 16% homozygous black Genetic variation is studied in populations. A gene pool consists of all genes, including all of the different alleles that are present in a population. Genetic variation is present within and between species of animals. Frequency of Alleles allele for brown fur allele for black fur 1. Describe the characteristics of two breeds of dogs. What variation is present within the species? 2. Compare the characteristics of frogs and earthworms. What variation is present between the species? 1. Answers will vary. Students may compare any two types of dogs, noting the variation present between the types. 2. Sample answers: Students may note the presence of limbs on a frog or differences in body systems between the species.

94 Evolution 75 California Biology/Life Science Standard *BI 7.e According to the Hardy-Weinberg principle, in order for genetic equilibrium to be maintained, five conditions must be met: 1. There must be random mating; 2. The population must be large; 3. There can be no movement into or out of the population; 4. There can be no mutations; and 5. There can be no natural selection. If all of these conditions are met, evolution will not occur. 1. Why can there be no movement into or out of the population? 2. Is it likely that all five conditions can be meet for long periods of time? 1. New organisms moving into the population will bring new alleles 2. No

95 Evolution 76 California Biology/Life Science Standard *BI 7.f The Hardy-Weinberg equation states: p + q = 1 where p = the frequency of one allele and q = the frequency of another allele. The three genotypes possible are: pp (p 2 ), pq, and qq (q 2 ). The equation that shows this is: p 2 + 2pq + q 2 = If p = 0.1, what does q equal? 2. What are the frequencies of the alleles p 2, 2pq, and q 2? 1. q = p 2 = 0.01, 2pq = 0.18, q 2 = 0.81

96 Evolution 77 California Biology/Life Science Standard BI 8.a Galápagos Islands Finches Shape of Head and Beak Common Name of Finch Species Vegetarian tree finch Large insectivorous tree finch Woodpecker finch Cactus ground finch Sharp-beaked ground finch Large ground finch Main Food Fruit Insects Insects Cactus Seeds Seeds Feeding Adaptation Parrotlike beak Grasping beak Uses cactus spines Large crushing beak Pointed crushing beak Large crushing beak Habitat Trees Trees Trees Ground Ground Ground An adaptation is a genetic change in an organism that helps it survive in its environment. The Galápagos finches likely descended from one population that became geographically isolated. 1. What helped the finches adapt to local food sources? 2. During a dry season, which finches may have a better chance of survival? 1. Changes to their beaks 2. Seed-eating

97 Evolution 78 California Biology/Life Science Standard BI 8.b Galápagos Islands Finches Shape of Head and Beak Common Name of Finch Species Vegetarian tree finch Large insectivorous tree finch Woodpecker finch Cactus ground finch Sharp-beaked ground finch Large ground finch Main Food Fruit Insects Insects Cactus Seeds Seeds Feeding Adaptation Parrotlike beak Grasping beak Uses cactus spines Large crushing beak Pointed crushing beak Large crushing beak Habitat Trees Trees Trees Ground Ground Ground A species traits may change over many generations due to environmental influences, such as changes in climate or landforms; interspecies interaction; and genetic mutations. Natural selection favors helpful traits in a way that increases the species fitness over time. 1. Is a parrotlike beak better adapted to feeding on fruit or insects? 2. What would likely happen to the population size of the vegetarian tree finch if trees on the island did not produce fruit one year? 1. Fruit 2. The population size would probably decline.

98 Evolution 79 California Biology/Life Science Standard BI 8.c Sample of Original Population Founding Population A Descendants Founding Population B Natural selection is not the only source of evolutionary change. Mutations, migration, genetic drift, and nonrandom mating can also result in evolution. In small populations, individuals that carry a particular allele may leave more descendants than other individuals, just by chance. Over time, a series of chance occurrences can cause an allele to become common in a population. 1. How do the descendant populations in the diagram differ from the original population? 2. What is genetic drift? 3. What is the founder effect? 1. They are different colors and have different markings. 2. A random change in allele frequency 3. A situation in which allele frequencies change as a result of a migration of a small subgroup of a population

99 Evolution 80 California Biology/Life Science Standard BI 8.d Miles Kilometers UTAH Lake Mead Grand Canyon ARIZONA Colorado Lake Powell River COLORADO NEW MEXICO Rio Grande Gila River Range of Kaibab squirrel Range of Abert squirrel Reproductive isolation occurs when members of two populations cannot interbreed. There are three types of reproductive isolation: behavioral isolation, geographic isolation, and temporal isolation. 1. What type of reproductive isolation has occurred when a barrier, such as a river, separates two populations? 2. When two populations are capable of breeding, but don t because of different courtship rituals, what type of reproductive isolation has occurred? 1. geographic isolation 2. behavioral isolation

100 Evolution 81 California Biology/Life Science Standard BI 8.e Nine-Banded Armadillo PACIFIC OCEAN NORTH AMERICA ATLANTIC OCEAN SOUTH AMERICA EUROPE AFRICA ASIA INDIAN OCEAN PACIFIC OCEAN AUSTRALIA Chinese Pangolin Common Echidna ANTARCTICA Giant Anteater Aardvark During the Paleozoic Era, the continents were one large landmass. As the continents drifted farther and farther apart, ancestors of mammal groups were isolated from one another. Mammals that feed on ants and termites evolved in five different regions. Question What characteristics do these mammals share? Front claws, long snout, and long tongue

101 Genetics 82 California Biology/Life Science Standard *BI 8.f RACCOONS LESSER PANDAS GIANT PANDAS BEARS The exact sequence of nitrogen bases in DNA is unique to each species. Organisms with similar DNA sequences are more closely related than those with different sequences. Present 10 million years ago 25 million years ago 40 million years ago COMMON ANCESTOR Comparing genes of different species helps to determine possible relationships among species. 1. Is the DNA of giant pandas more similar to the DNA of bears or lesser pandas? 2. When did all four groups share an ancestor? 3. Which have more similar DNA sequences, raccoons and lesser pandas or giant pandas and bears? 1. Bears 2. More than 40 million years ago 3. Giant pandas and bears

102 Evolution 83 California Biology/Life Science Standard *BI 8.g Animal Species Amino Acid Sequence of Cytochrome C Human GDVEK GKKIF IMKCS QCHTV EKGGK HKTGP NLHGL FGRKT GQAPG YSYTA ANKNK GIIWG Donkey GDVEK GKKIF VQKCA QCHTV EKGGK HKTGP NLHGL FGRKT GQAPG FSYTD ANKNK GITWK Horse GDVEK GKKIF VQKCA QCHTV EKGGK HKTGP NLHGL FGRKT GQAPG FTYTD ANKNK GITWK Chicken GDIED GKKIF VQKCS QCHTV EKGGK HKTGP NLHGL FGRKT GQAEG FSYTD ANKNK GITWG Turkey GDIEK GKKIF VQKCS QCHTV EKGGK HKTGP NLHGL FGRKT GQAEG FSYTD ANKNK GITWG Rattlesnake GDVEK GKKIF TMKCS QCHTV EKGGK HKTGP NLHGL FGRKT GQAVG YSYTA ANKNK GITWG G=glycine, A=alanine, V=valine, L=leucine, I=isoleucine, M=methionine, F=phenylalanine, W=tryptophan, P=proline, S=serine, T=threonine, C=cysteine, Y=tyrosine, N=asparagine, Q=glutamine, D=aspartate, E=glutamate, K=lysine, R=arginine, H=histidine Many genes are shared by a wide range of organisms. Cytochrome c is a protein found in most eukaryotic cells. The more closely two organisms are related, the more closely their genes resemble one another. 1. Is a turkey more closely related to a chicken or to a rattlesnake? How can you tell? 2. With which animal does a donkey share the most recent ancestor? 1. a chicken because they have more amino acid sequences in common 2. horse

103 Physiology 84 California Biology/Life Science Standard 7 5.a Muscle cell Smooth muscle tissue Stomach Digestive system The four levels of organization in a multicellular organism include cells, tissues, organs, and organ systems. Organ systems work together to maintain homeostasis in the body as a whole. 1. How does the human digestive system contribute to homeostasis in the body? 2. How does the term division of labor apply to the organ systems of the bodies of multicellular organisms? 1. It provides the nutrients required for the body to function. 2. Organ systems are specialized, and each performs only a fraction of the functions required for maintenance of homeostasis in the body as a whole.

104 Physiology 85 California Biology/Life Science Standard 7 5.a Leaf Plants are multicellular eukaryotes that have cell walls made of cellulose. Plants have the same levels of organization as animals cells, tissues, organs, and organ systems. Stem Plants consist of three main tissue systems: dermal tissue, vascular tissue, and ground tissue. Root 1. For what process do plants require sunlight? Dermal tissue Vascular tissue Ground tissue 2. What human organ could be compared to the dermal tissue of a plant? 1. Photosynthesis 2. Skin

105 Physiology 86 California Biology/Life Science Standard 7 5.c Movement Movement Biceps (relaxed) Biceps Triceps (contracted) Triceps Skeletal muscles generate force and produce movement by pulling on body parts. Skeletal muscles are joined to bones by tendons. Tendons pull on bones and make them work like levers. Most skeletal muscles work in opposing pairs. 1. When the arm bends, which muscle is relaxed? Which is contracted? 2. In the example shown, what is the fulcrum (the point around which the lever moves)? 1. Triceps, biceps 2. The elbow

106 Physiology 87 California Biology/Life Science Standard 7 6.j The structure of an organ is adapted to perform specific functions within one or more systems. The circulatory system consists of the heart, blood vessels, and blood. The circulatory system interacts with the respiratory system to provide the body with oxygen. Valves keep blood moving in one direction. 1. What is the role of the heart in the circulatory system? 2. Is the blood that travels to the lungs oxygen-rich or oxygen-poor? How about the blood that leaves the lungs? 1. It pumps blood through the system. 2. Oxygen-poor; oxygen-rich

107 Physiology 88 California Biology/Life Science Standard BI 9.a Circulatory System Structures: Heart, blood vessels, blood Function: Brings oxygen, nutrients, and hormones to cells; fights infection; removes cell wastes; helps to regulate body temperature In animals, organ systems are interdependent. Organ systems work together in many functions; for example, delivering oxygen to tissues requires both the respiratory system and the circulatory system. Respiratory System Structures: Nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs Function: Provides oxygen needed for cellular respiration and removes excess carbon dioxide from the body Digestive System Structures: Mouth, pharynx, esophagus, stomach, small and large intestines; rectum Function: Converts foods into simpler molecules that can be used by the cells of the body; absorbs food; eliminates wastes 1. What body system removes wastes from the cells? 2. What two organ systems are needed to deliver nutrients to cells? 1. Circulatory system 2. Digestive and circulatory systems

108 Physiology 89 California Biology/Life Science Standard BI 9.b Pituitary Gland Hormones Pituitary Gland Posterior pituitary Anterior pituitary The nervous system and endocrine system work together to coordinate body activities. The endocrine system is made up of glands that release hormones into the bloodstream. Hormones deliver messages throughout the body. The endocrine system is regulated by feedback loops that function to maintain homeostasis in the body. Hormone Antidiuretic hormone (ADH) Oxytocin Follicle-stimulating hormone (FSH) Luteinizing hormone (LH) Thyroid-stimulating hormone (TSH) Adreno-corticotropic hormone (ACTH) Growth hormone (GH) Prolactin Melanocyte-stimulating hormone (MSH) Action Stimulates the kidneys to reabsorb water from the collecting tubules Stimulates contractions of uterus during childbirth; releases milk in nursing mothers Stimulates production of mature eggs and sperm Stimulates ovaries and testes; prepares uterus for implantation of fertilized egg Stimulates the synthesis and release of thyroxine from the thyroid gland Stimulates release of some hormones from the adrenal cortex Stimulates protein synthesis and growth in cells Stimulates milk production in nursing mothers Stimulates the melanocytes of the skin, increasing their production of the skin pigment melanin 1. How does the body s response to hormones compare to the body s response to nerve impulses? 2. Why is the health of the endocrine system important to the overall health of the body? 1. Response to hormones is usually slower to occur and longer lasting than response to a nerve impulse. 2. The endocrine system maintains homeostasis, which is vital to the health of the body.

109 Physiology 90 California Biology/Life Science Standard BI 9.c Homeostasis is the process by which organisms keep internal conditions fairly constant despite changes in the external environment. Some unicellular organisms maintain homeostasis through the use of organelles. Others produce spores that can survive environmental conditions that are unfavorable for growth. Most multicellular organisms use feedback loops to help maintain homeostasis. 1. Why is it important for organisms to maintain a relatively constant internal environment? 2. How does feedback inhibition work? 3. What endocrine gland in the human body is primarily responsible for maintaining homeostasis? 1. Most organisms need to keep internal conditions fairly constant to survive. 2. It turns a particular body process off once the condition it produces reaches a specific level. 3. The hypothalamus

110 Physiology 91 California Biology/Life Science Standard BI 9.d Nucleus Axon terminals Cell body Myelin sheath Nodes Axon Dendrites The nervous system controls and coordinates functions throughout the body and responds to internal and external stimuli. Messages carried by the nervous system are called impulses. The cells that transmit these impulses are called neurons. 1. What type of cell is shown in the drawing? 2. What is the function of the cell shown in the drawing? 3. Chemicals used by neurons to transmit an impulse across a synapse to another cell are. 1. A neuron 2. Neurons transmit electrical and chemical messages. 3. neurotransmitters

111 Physiology 92 California Biology/Life Science Standard BI 9.e Sensory neuron Motor neuron Interneuron Spinal cord Effector (responding muscle) Neurons are classified into three types according to the direction in which an impulse travels. Sensory neurons carry impulses from the sense organs to the spinal cord and brain. Motor neurons carry impulses from the brain and spinal cord to muscles and glands. Interneurons connect sensory and motor neurons and carry impulses between them. Sensory receptors 1. What two organ systems allow a response to stepping on a tack? 2. Where are interneurons located? Tack 1. Nervous and muscular systems 2. In the spinal cord

112 Physiology 93 California Biology/Life Science Standard *BI 9.f Active Site Enzyme Effect on Food Mouth Stomach Small intestine (from pancreas) Effects of Digestive Enzymes Salivary amylase Pepsin Amylase Trypsin Breaks down starches into disaccharides Breaks down proteins into large peptides Continues the breakdown of starch Continues the breakdown of protein Digestion involves physical and chemical changes. Mechanical digestion is the physical breakdown of large pieces of food into smaller pieces. During chemical digestion, large food molecules are broken down into smaller food molecules. Small intestine Lipase Maltase, sucrase, lactase Peptidase Breaks down fat Breaks down remaining disaccharides into monosaccharides Breaks down dipeptides into amino acids 1. Which type of digestion involves digestive enzymes? 2. Where does the digestion of starch begin? 3. Where does the digestion of fat begin? 1. Chemical digestion 2. Mouth 3. small intestine

113 Physiology 94 California Biology/Life Science Standard *BI 9.g Kidney Nephron Cortex Medulla Bowman s capsule Glomerulus Renal artery Capillaries Renal vein To the bladder Ureter Vein Artery Loop of Henle Collecting duct To the ureter The kidneys are the main organs of the human excretory system. Nephrons in the kidneys control the composition, volume, and ph of blood. Most of the materials removed from the blood during filtration are reabsorbed. 1. What system does the blood belong to? 2. What happens to the wastes that are not reabsorbed back into the blood? 1. Circulatory system 2. They end up in the collecting duct.

114 Physiology 95 California Biology/Life Science Standard *BI 9.h Actin Movement of Actin Filament Binding sites Myosin Cross-bridge ATP A muscle contracts when the thin filaments in the muscle fiber (actin) slide over the thick filaments in the muscle fiber (myosin). ATP supplies the energy for muscle contraction. 1. What is actin? What is myosin? 2. Where in the cell is ATP produced? 3. What are the two ways a cell can produce ATP? 1. Actin: thin filaments in skeletal muscle; myosin: thick filaments in skeletal muscle 2. mitochondria 3. cellular respiration and fermentation

115 Physiology 96 California Biology/Life Science Standard *BI 9.i The endocrine system is made up of glands that release hormones into the bloodstream. Hormones deliver messages throughout the body. The endocrine system is regulated by feedback mechanisms that function to maintain homeostasis in the body. Endocrine System Structures: Hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, ovaries (in females), testes (in males) Function: Controls growth, development, and metabolism; maintains homeostasis The hormones insulin and glucagon help keep the level of glucose in the blood stable. Insulin stimulates cells in the liver to remove sugar from the blood. Glucagon stimulates the liver to release glucose back into the blood. 1. What hormone is released after you eat a meal? 2. What happens when low blood sugar is detected? 1. Insulin 2. The production of glucagon is stimulated

116 Physiology 97 California Biology/Life Science Standard BI 10.a Hair Epidermis Pore Oil gland Dermis Sweat gland Fat Hair follicle Nerve Muscle Blood vessels The body s first line of defense against infection is barriers such as the skin, breathing passages, mouth, and stomach. The body s second line of defense is the inflammatory response. The body s third line of defense is the immune response. 1. What happens when the skin is broken? 2. What is the inflammatory response? 1. Pathogens enter the body and multiple. 2. The body responds by leaking fluid and white blood cells from blood vessels into tissues.

117 Physiology 98 California Biology/Life Science Standard BI 10.b Antigen-binding sites Antigen Antibody The immune system includes two categories of defense mechanisms against infection: nonspecific defenses and specific defenses. Antibodies are proteins that recognize and bind to antigens. Antibodies have two identical antigen-binding sites. Small differences in the antigen-binding sites make it possible for the antibody to recognize a specific antigen. Question Is the production of antibodies a specific or nonspecific defense against infection? Specific

118 Physiology 99 California Biology/Life Science Standard BI 10.c Vaccination Vaccine Skin Weakened or killed pathogen Antibody Antibody Real pathogen 1 A person receives an injection with weakened or killed pathogens. 2 The immune system produces antibodies against the disease. It also produces memory cells. 3 If the real pathogen invades later, memory cells help to produce antibodies that disable the pathogen. Louis Pasteur found that after a body became infected with germs, it could become immune to another infection by the same germs. He also showed that vaccines could cause the body to become immune to a disease without causing the disease. Vaccines are used to prevent diseases. Antibiotics are used to treat bacterial infections. 1. What type of immunity do vaccines produce? 2. If you have been vaccinated against measles, is it likely that you will become infected with the measles? 1. Active 2. No

119 Physiology 100 California Biology/Life Science Standard BI 10.d Living organisms must maintain a relatively stable internal environment in order to live. Stability is challenged by the presence of disease-agents, such as viruses. Viruses cause a wide range of human diseases including yellow fever, the common cold, polio, mumps, and AIDS. Peptidoglycan Cell wall Cell membrane Ribosome The proteins on the surface of a virus specifically fit the proteins on the surface of the cell it infects. 1. What do all viruses have in common? Flagellum DNA Pili 2. To which life process does flagellum contribute? 1. Viruses enter living cells and exploit host machinery to replicate. 2. Response to the environment (locomotion)

120 Physiology 101 California Biology/Life Science Standard BI 10.d Common Diseases Caused by Bacteria Disease Pathogen Prevention Tooth decay Streptococcus mutans Regular dental hygiene Lyme disease Tetanus Tuberculosis Salmonella food poisoning Pneumonia Cholera Borrelia burgdorferi Clostridium tetani Mycobacterium tuberculosis Salmonella enteritidis Streptococcus pneumoniae Vibrio cholerae Protection from tick bites Current tetanus vaccination Vaccination Proper food-handling practices Maintaining good health Clean water supplies Some bacteria can cause disease, by breaking down host tissue for food or by releasing harmful toxins. Bacterial toxins can spread throughout the body (as in tetanus and food poisoning). Antibiotics interfere with the life cycle of bacteria, and are used to treat bacterial infections. Sterilization destroys bacteria by subjecting them to great heat or to chemical action. 1. How can bacterial infections be prevented? 2. What happens when many people drink from the same water supply contaminated with cholera bacteria? 1. Through good hygiene and vaccinations 2. An epidemic arises.

121 Physiology 102 California Biology/Life Science Standard BI 10.e Capsid Protein coat Viral RNA Envelope Reverse transcriptase enzyme HIV is a retrovirus it caries its genetic information in RNA rather than in DNA. HIV attacks helper T cells and enters the cell. Once inside, it forces the host cell to make DNA copies of the virus s RNA. As the HIV particles reproduce, they kill more and more helper T cells. Eventually this cripples the immune system. 1. Physicians count the number of helper T cells to check the progress of HIV infection. What does a low number of helper T cells indicate? 2. Why might a person with HIV get sick faster than a healthy person? 1. That the disease is more advanced. 2. Because the immune system is weakened and can t fight off pathogens as easily.

122 Physiology 103 California Biology/Life Science Standard BI 10.f Superior vena cava Thymus White blood cells guard against infection, fight parasites, and attack bacteria. Heart Thoracic duct Spleen Lymph nodes Lymph vessels One type of white blood cell, called phagocytes, engulf and digest bacteria. Another type of white blood cell, called lymphocytes, produce antibodies. Lymphocytes called T cells mature in the thymus before they can function in the immune system. 1. What does an increase in white blood cell count indicate? 2. To what two body systems do white blood cells belong? 1. the body is fighting an infection 2. circulatory system, immune system

123 Physiology 104 California Biology/Life Science Standard *BI 10.f Macrophage Antigens are displayed on surface of macrophage. T cell, activated by macrophage, becomes a helper T cell. Helper T Cell T cell binds to activated macrophage. T Cell Helper T cell activates killer T cells and B cells. There are two types of lymphocytes: B lymphocytes (B cells) and T lymphocytes (T cells). B cells provide immunity against antigens and pathogens in the blood. T cells provide defense against abnormal cells and pathogens inside living cells. T cells differentiate into killer T cells, helper T cells, and memory T cells. Infected Cell Killer T Cell Killer T cells bind to infected cells, disrupting their cell membranes and destroying them. 1. What type of T cell actives killer T cells? 2. What type of T cells destroys the tissue that contains an antigen? 3. What might happen if the same antigen enters the body a second time? 1. helper T cells 2. killer T cells 3. the body produces a secondary response

124 Investigation and Experimentation 105 California Biology/Life Science Standard 6IIE 7.c Oxygen Production of a Water Plant Distance From Light (cm) Bubbles Produced per Minute Scientific data can be qualitative (descriptive): The bird has a red head. Data can also be quantitative (involving numbers or measurements): The cat has three kittens. After collecting data for an experiment, you need to organize it in a way that makes it useful, such as putting it in a table format. Scientists often convert tables of data into graphs in order to identify patterns and trends. 1. What type of graph would best represent the data in the table? Why? 2. About how many bubbles would you expect would be produced at a distance of 20.5 cm? 3. Using only this data, can you reasonably infer that the changing distance from the light is what affected bubble production? Explain. 1. A line graph. Line graphs are used to show how one variable changes in response to another variable. 2. About No. For example, the light likely gives off heat. The bubble production may be affected by changing temperature rather than by the light itself.

125 A Time to Fill a 1-gallon Pot With Water Flow Rate (gallons per minute) Investigation and Experimentation 106 California Biology/Life Science Standard 6IIE 7.c Time (minutes) Scientific data can be organized using tables and graphs. B Average Annual Precipitation for Selected U.S. Cities Line graphs are useful for showing changes that occur in related variables. Bar graphs are used to compare a set of measurements, amounts, or changes. Average Annual Precipitation (cm) Circle graphs show how parts relate to a whole. Buffalo Chicago Colorado Springs Houston San Diego Tallahassee Tucson C Composition of Earth s Crust Silicon 27.7% Oxygen 46.6% Aluminum 8.1% Iron 5.0% 30.5 Calcium 3.6% Sodium 2.8% Potassium 2.6% Magnesium 2.1% Other 1.5% 1. Why are graphs a useful tool for organizing data? 2. What type of graph would be best to show the relationship between the pressure on a gas and its volume? 1. They allow you to see the relationships between variables, spot trends, and interpret results. 2. A line graph

126 Investigation and Experimentation 107 California Biology/Life Science Standard 6IIE 7.c Effect of Temperature on Seed Germination Germination (%) Seeds from Clinton, Ontario Seeds from Baton Rouge, LA Stored at 24 C Stored at 3 C Keep your hypothesis in mind when you are drawing conclusions. Do the data support the hypothesis or not? Compile your results and make them accessible to others. A conclusion may leave you with another question that you could test with another experiment. 1. If your conclusion does not support your hypothesis, is it necessarily an invalid conclusion? Explain. 2. Draw a conclusion from the data in the bar graph above. 1. No. In science, finding out that two events are not related is often as important as finding out they are related. Such results contribute to a scientist s body of knowledge. 2. Sample answer: Seeds from Clinton have a higher rate of germination when chilled, whereas the germination of seeds from Baton Rouge is not affected by chilling.

127 Investigation and Experimentation 108 California Biology/Life Science Standard 7IIE 7.c A conclusion is a final statement summing up the results of the experiment. Scientists often repeat experiments and compare their results with the results of other scientists before they trust a conclusion. Conclusions often leave a scientist with new questions, which can be investigated in other controlled experiments. 1. What is the main factor you need to keep in mind when drawing a conclusion? Explain. 2. If the two plants received different amounts of fertilizer, would you be able to draw a valid conclusion about what made one plant grow more than the other? Explain. 1. The original hypothesis. You need to decide whether or not the data support the hypothesis. 2. No. There would be no way to tell whether the amount of light or the amount of fertilizer or both caused one plant to grow more than the other.

128 Investigation and Experimentation 109 California Biology/Life Science Standard 8IIE 9.b EXPERIMENTAL PROCEDURE 1. Fill 3 containers with 300 milliliters of cold tap water. 2. Add 10 grams of salt to Container 1; stir. Add 20 grams of salt to Container 2; stir. Add no salt to Container Place the 3 containers in a freezer. 4. Check the containers every 15 minutes. Record your observations. Scientists conduct experiments to learn about events and processes. Although experiments differ, many follow a pattern. Scientists begin by posing questions and then forming a hypothesis, or prediction, of the outcome. All variables except one must be controlled, and the one being changed is the manipulated variable. Data is collected by observation and measurement. It must then be interpreted in order to draw a conclusion, a summary statement of what has been learned. 1. What question could the experiment described here be designed to answer? 2. What are the controlled variables and the manipulated variable in this experiment? 3. What conclusion are the data likely to support? 1. Which freezes faster fresh water or salt water? 2. Amount of water, starting temperature of the water, and temperature of the freezer; amount of salt added to the water 3. Fresh water freezes faster than salt water.

129 Investigation and Experimentation 110 California Biology/Life Science Standard 8IIE 9.c Redi s Experiment on Spontaneous Generation OBSERVATIONS: Flies land on meat that is left uncovered. Later, maggots appear on the meat. HYPOTHESIS: Flies produce maggots. PROCEDURE Uncovered jars Covered jars Controlled Variables: jars, type of meat, location, temperature, time Manipulated Variable: gauze covering that keeps flies away from meat Several days pass. Scientific experiments have three types of variables: manipulated variables, responding variables, and controlled variables. A carefully designed experiment tests only one variable at a time. Maggots appear. CONCLUSION: Maggots form only when flies come in contact with meat. Spontaneous generation of maggots did not occur. No maggots appear. 1. Why is it important to change only one variable at a time in an experiment? 2. What was the responding variable in Redi s experiment? 1. So you can be sure that any changes in the responding variable are due to changes in the manipulated variable. 2. whether or not maggots appear

130 Investigation and Experimentation 111 California Biology/Life Science Standard BIIE 1.a Kinds of Pets Owned by Families Number of Pet Families Dogs Cats Birds Fish Other* 110 *Includes gerbils, hamsters, rabbits, guinea pigs, and ferrets The same data can be organized differently depending on what the researcher is investigating. Less detailed organization: Mammals (Dogs, Cats, and Other combined), Birds, and Fish More detailed organization: German shepherds, Irish setters, and Poodles (instead of Dogs). 1. Can you infer from the data that people do not like having lizards as pets? Explain. 2. Are there the same number of birds owned as there are fish owned? Explain. 3. If you surveyed another 100 families, about how many would you expect to own dogs? Explain. 1. No. Maybe lizards just weren t covered in the survey. 2. There is no way to tell. The table shows that 25 families own birds and 25 own fish. But it does not say how many birds or fish each family has. 3. About 36. Because 180 of 500 families own dogs, you could reasonably predict that about 36 of the next 100 families would own dogs

131 Investigation and Experimentation 112 California Biology/Life Science Standard BIIE 1.b City Temperatures January High January Low July High July Low City A 26 C 18 C 28 C 20 C City B 32 C 10 C 44 C 27 C Scientists review their data critically, looking for possible sources of error. In science, error refers to the differences between observed results and true values. Experimental error can result from human mistakes or problems with equipment. Appropriate data answer the questions being asked in the investigations. 1. Name two possible sources of error for the data in the data table above. 2. Are the data in the data table appropriate for analyzing year-round temperature variation in city A? Why or why not? 1. Sample answer: Inaccurate thermometers; human error reading the thermometers 2. No, the data only show temperatures for two months; they are not appropriate for analyzing year-round temperatures in city A.

132 Investigation and Experimentation 113 California Biology/Life Science Standard BIIE 1.c Scientific investigations begin with a question about the natural world. A useful hypothesis leads to testable predictions. Results may vary if conditions are not controlled. 1. What hypothesis is being tested in the illustration? 2. What are some other sources of heat that could be used to test the same hypothesis? 3. Why does a properly designed experiment call for only one independent variable to change at a time? 1. Does the shape of a block of ice affect the time it takes for the ice to melt? 2. Answers will vary. Samples: Room temperature; an oven; a stovetop; a hotplate 3. If more than one independent variable changed at a time, there would be no way to tell which change affected the dependent variable.

133 Investigation and Experimentation 114 California Biology/Life Science Standard BIIE 1.d CO 2 in Atmosphere Photosynthesis Volcanic activity Feeding Respiration Decomposition Human activity CO 2 in Ocean Respiration Erosion Uplift Deposition Photosynthesis Feeding Fossil fuels Deposition Carbonate rocks At times, the environmental conditions are such that plants and marine organisms grow faster than decomposers can recycle them back to the environment. Millions of years ago, layers of energy-rich organic material were gradually turned into coal beds and oil pools by the pressure of the overlying earth. By burning fossil fuels, such as coal and oil, people are passing most of the stored energy back into the environment as heat and releasing large amounts of carbon dioxide. 1. What are three activities that release carbon dioxide into the atmosphere? 2. Which processes take in carbon dioxide? 3. As carbon dioxide concentrations increase in the atmosphere, what is happening to global temperatures? 1. Answers include volcanic activity, breathing, and burning fossil fuels 2. Photosynthesis 3. They are getting warmer (global warming).

134 Investigation and Experimentation 115 California Biology/Life Science Standard BIIE 1.e Boiling Time of Water by Volume 40 Boiling Time (min) ,000 1,500 2,000 Volume of Water (ml) Scientists use mathematical expressions and techniques to explain data and observations and to communicate the results of an experiment. A formula is a rule written as an equation with symbols or variables that describes the relationship between quantities. Scientists also use formulas to calculate quantities. The values obtained from an equation can be plotted on a graph. The points on a graph can be connected to show a pattern, or a relationship between the two variables. 1. Is the relationship between the two variables direct or inverse? How do you know? 2. What are estimates based on? 3. What is the mean of a set of data? 1. Direct; as one variable increases, so does the other one; the line goes upward. This also makes physical sense. 2. Known information and reasonable assumptions. 3. The numerical average

135 Investigation and Experimentation 116 California Biology/Life Science Standard BIIE 1.f A hypothesis is a proposed scientific explanation for a set of observations. Scientists generate hypotheses using prior knowledge as well as informed inference. Scientific hypotheses must be proposed in a way that enables them to be tested. In science, the word theory applies to a well-tested explanation that unifies a broad range of observations. A theory allows scientists to make accurate predictions about new situations. 1. How does a scientific theory compare with a scientific hypothesis? 2. Can theories change over time? 1. A hypothesis is a proposed scientific explanation for a set of observations, whereas a theory is a well-tested explanation that unifies a broad range of observations. 2. Yes, theories can change as new data are gathered and new ways of thinking arise.

136 Investigation and Experimentation 117 California Biology/Life Science Standard BIIE 1.g Ratio of Surface Area to Volume in Cells Cell Size Surface Area (length x width x 6) Volume 1 cm x 1 cm x 1 cm (length x width x height) = 1 cm 3 Ratio of Surface Area to 6 / 1 = 6 : 1 Volume 1 cm 2 cm 3 cm 1 cm 1 cm 2 cm 2 cm 3 cm 3 cm 1 cm x 1 cm x 6 = 6 cm 2 2 cm x 2 cm x 6 = 24 cm 2 3 cm x 3 cm x 6 = 54 cm 2 2 cm x 2 cm x 2 cm = 8 cm 3 24 / 8 = 3 : 1 3 cm x 3 cm x 3 cm = 27 cm 3 54 / 27 = 2 : 1 A model is a physical or mental representation of an object, process, or event. Models are used to help people understand natural objects and how processes affect those objects. Mathematical models generally involve numerical data or measurements. 1. What conclusion can be drawn from the model of the cell shown in the diagram? 2. Why might this model be useful? 3. How might computers make mathematical models more useful? 1. As the length of a cell increases, its volume increases faster than its surface area. 2. To show that the size of a cell is limited by the materials that can pass through its surface. 3. They can compute large amounts of data and show changes over time.

137 Investigation and Experimentation 118 California Biology/Life Science Standard BIIE 1.h Topographic maps provide accurate information on the elevation, relief, and slope of the ground surface using contour lines. Most topographic maps are large-scale maps that show a close-up view of part of Earth s surface. Mapmakers use symbols to represent natural and constructed features, such as highways, rivers, buildings, and woods. 1. In the United States, what agency is responsible for producing topographic maps? 2. On a 1:25,000 scale map, how much distance on land is represented by 1 cm on the map? 3. On a map what symbol represents a campground? 1. The U.S. Geological Survey (USGS) 2. 25,000 cm or 0.25 km 3. A tent

138 Investigation and Experimentation 119 California Biology/Life Science Standard BIIE 1.i Scientists often use methods other than radioactive dating to determine the relative and absolute ages of rocks. Geologists determine the relative age of some rocks by their depth. Rock layers near the surface are younger than deeper ones. The absolute age of a rock sample can be determined using index fossils. These remains are of organisms that lived for only a brief time, so they can be used to date the rock layers. 1. Which rock layer at Location 1 is the youngest? The oldest? 2. At Location 2, which layers contain index fossils? 3. How do you know that Layer C rocks in Locations 1, 2, and 4 are actually the same age? 1. Layer D is the youngest; Layer A is the oldest. 2. Layers A and C 3. They all contain the same index fossil.

139 Investigation and Experimentation 120 California Biology/Life Science Standard BIIE 1.j In a controlled experiment, all conditions are the same except the manipulated variable. In an experiment testing how light affects plant growth you have to control any variables that affects growth, except light. Question Using the experiment shown above, classify each of these variables as either a manipulated variable or responding variables: a. kind of plant b. type of container c. type and amount of soil d. type and amount of fertilizer e. amount of water added f. amount and source of lighting All are responding variables except (f) the amount and source of lighting

140 Investigation and Experimentation 121 California Biology/Life Science Standard BIIE 1.k! Prior to the studies of Charles Darwin, the most widespread belief was that all known species were created at the same time and remained unchanged throughout history. Some scientists at the time believed that features an individual acquired during a lifetime could be passed on to its offspring. According to this idea, a species could gradually change and fit an environment better. 1. Who proposed that selective use or disuse of an organ could affect the traits that an organism passes on to offspring? 2. What explanation for changes in species does the figure show? 3. How is the explanation of evolution shown in the figure similar to Darwin s explanation? 1. Lamarck 2. By using the front claw over and over, the crab s claw grew larger. A large front claw was then passed on to the crab s offspring. 3. Both explanations recognize that living things have changed over time.

141 Investigation and Experimentation 122 California Biology/Life Science Standard BIIE 1.l Herbal remedies are available in many stores. They are available without prescriptions. The Food and Drug Administration cannot require studies of the safety and effectiveness of herbal remedies and supplements. Advocates of herbal remedies note that herbal products have been used safely by many cultures for thousands of years. It is important to carefully evaluate the advertising claims of any supplement. 1. Name two specific ways you could evaluate an advertising claim made about an herbal remedy. 2. Compare the reliability of advertising claims about a product to the reliability of scientific studies of a product s safety and effectiveness. 1. Sample answer: Talk to family doctor; do research using reliable sources. 2. Answers will vary, but students should note that scientific studies are more reliable than advertising claims.

142 Investigation and Experimentation 123 California Biology/Life Science Standard BIIE 1.m Genetically modified (GM) plants are engineered to contain chemicals that resist weeds or kill pests. Advantages: More food can be grown on fewer acres of land. Foods can be modified to contain nutrients that can help ease famine and malnutrition. GM plants could be a source of medicine or fuel. Disadvantages: GM plants used as animal feed could get into food meant for humans, causing health problems. Natural insecticides can kill beneficial insects as well as pests. Traits of GM plants could be passed on to other plants, creating weeds strongly resistant to pesticides and endangering species that feed on them. 1. Do you think we should use GM plants? What factor(s) most affected your decision? Present your answer to the class orally. 2. What factors other than those mentioned here might you consider when making your decision? 1. Answers will vary. Students should include the factors that support their position, as well as their reasons for weighing some factors more heavily than others. They should represent their position from a scientific perspective. 2. Sample responses: Economic considerations, such as the cost of health care, of fighting hunger and disease, of farmland. Climate considerations, such as being able to grow food that would withstand drought or other harsh conditions.

143 Investigation and Experimentation 124 California Biology/Life Science Standard BIIE 1.n Hypotheses and theories can be analyzed using the results of investigations and previous knowledge. In 1809, Lamarck proposed that the use or disuse of a particular organ could alter the size or shape of that organ over generations. Although Lamarck s hypotheses were incorrect in several ways, he did realize that organisms are adapted to their environments. 1. Can an incorrect hypothesis, such as Lamarck s, contribute to scientific progress? Explain. 2. Lamarck s hypotheses were based on observations. Describe an investigation or experiment that could test Lamarck s hypotheses. 1. Sample answer: Yes, other scientists can use the strengths, or correct portions, to advance their own work. 2. Sample answer: Develop a characteristic, such as obesity, in lab mice and measure whether the trait is passed to offspring.