Name: Class: Biology Weekly Packet January th, 2013 Tuesday January 22, 2013

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1 Name: Class: Biology Weekly Packet January th, 2013 Tuesday January 22, 2013 Graphs The x- axis is horizontal and is the dependent variable. The y- axis is vertical and is the independent variable. The picture above is of an increasing graph. The picture above is of a decreasing graph. Sex- Linked Traits Females have XX for sex chromosomes, while males have XY. X- linked traits are ONLY on the X chromosomes, so females have two, just like autosomal traits, but males only have one. Since males only have one, they HAVE TO express that trait. A carrier is someone (usually a woman) who has one allele for the recessive trait (she carries the trait) but also one allele for the dominant trait, so she does not express the recessive trait. We also know this as heterozygous. Catalyst 1. An ecologist performed a study to determine how the rate of photosynthetic activity in a lake changed from month to month. The results of the study are shown in the graph below. Which conclusion is best supported by the evidence? A. Photosynthetic organisms were dormant during the months of April through August. B. The rate of photosynthesis increase from June through December. C. The rate of photosynthesis was greatest during the months of May through July. D. Photosynthetic organisms experienced die- off during the months of January through June. 2. The graph represents the relationship between an organism s oxygen consumption and body mass. Which statement is supported by the information shown in the graph? A. The oxygen consumption of an organism is one- half its body mass. B. The oxygen consumption of an organism is not related to its body mass. C. As the body mass of an organism increase, oxygen consumption decreases. D. As the body mass of an organism decreases, oxygen consumption decreases.

2 3. Hemophilia is a sex- linked trait found on the X chromosome. To get this disease, a person must have a recessive copy of the gene (h) on every X chromosome. Predict the genotypic and phenotypic PERCENTAGES of the offspring if a woman who was a carrier for the disease had a baby with a man who does have the disease. Genotype of mother: Genotype of father: Genotype= Phenotype= Wednesday January 23, 2013 Prokaryotic vs. Eukaryotic Cells Prokaryotic cells have no nucleus or membrane- bound organelles. They often have a flagella or cilia and a cell wall. They are small, single- celled organisms which carry out only simple life processes. The kingdoms Bacteria and Archeabacteria include prokaryotic organisms. Eukaryotic cells have a membrane- bound nucleus and membrane- bound organelles. They are larger and often compose multi- cellular organisms. They can carry out more complex life processes. The kingdoms Fungi, Protista, Plantae, and Animalia include eukaryotic organisms. Dihybrid Crosses Dihybrid crosses allow us to predict TWO traits at the same time. In order to correctly predict the offsprings traits we must use the FOIL method to distribute each allele. Catalyst 1. Two cells are shown in the diagrams below. Cell 1 Cell 2 Which statement correctly identifies the cells? A. Cell 1 is prokaryotic; cell 2 is eukaryotic. B. Cell 1 is eukaryotic; cell 2 is prokaryotic. C. Both cells are prokaryotic. D. Both cells are eukaryotic. 2. Which best explains why a bacterial cell is classified as a prokaryote? A. the presence of a nucleus B. the absence of a nucleus C. the presence of a cell wall D. the absence of a cell wall

3 3. These letters represent the genotypes of dogs: B- black hair b- brown hair L- long ears l- short ears What are the phenotypes of dogs that have the following genotypes: Bbll BBLL 4. Using the FOIL method, list the four gametes that would be produced from the following parental genotypes: Bbll BBLL First: First: Outer: Outer: Inner: Inner: Last: Last: Thursday January 24, 2013 Enzymes Enzymes are proteins that are catalysts for cellular reactions. They increase the reaction rate by lowering the activation energy required for a reaction to take place. Substrates attach to the active site on the enzyme, the reaction occurs, and the product leaves the enzyme. The enzyme IS NOT changed during the reaction and can be reused over and over. Temperature, ph, and concentration can affect how well an enzyme will work. Patterns in Punnett Squares - A cross between a homozygous dominant organism and a homozygous recessive organism will always result in ALL offspring being heterozygous. - A cross between two heterozygous organisms will always result in the 1:2:1 ratio of homozygous dominant : heterozygous : homozygous recessive. Catalyst 1. Which best describes how enzymes function in the body? A. Enzymes are converted into products by the reactions they catalyze. B. Enzymes lower the activation energy of reactions. C. One enzyme can catalyze many different reactions. D. An enzyme is used once and then destroyed by the cell. 2. Which best describes the role of enzymes in a chemical reaction? A. absorb excess energy B. release unused energy C. increase the reaction rate D. regulate product reactivity 3. What is the percent of offspring that will be heterozygous for both traits in a cross between a female who is AABB and a male who is aabb? A. 0% B. 25% C. 50% D. 100%

4 Friday January 25, 2013 Scientific Method 1. Make an observation or ask a question. 2. Gather information. 3. Create a hypothesis: an educated prediction of what is going to happen. 4. Design and conduct an experiment. 5. Analyze the data. 6. Draw a conclusion. Pedigrees - Squares represent males. - Circles represent females. - Shaded in squares or circles represent the trait. - Heterozygous individuals WILL NOT show recessive traits. - Recessive traits will ONLY be shown with homozygous. - Start by assigning recessive traits and working backwards to determine the genotypes of other individuals. 1. An inventor has an idea for a pest control product for farms. The inventor proceeds to build and market the product. Which step in the engineering design process has the inventor neglected to do? A. identify a need B. define the problem C. narrow the research D. verify the results 2. When designing a scientific investigation, which of the following should be identified first? A. lab equipment needed B. appropriate sample size C. useful analysis software D. a testable hypothesis 3. The following pedigree represents which type of trait? A. Autosomal dominant B. Autosomal recessive C. Sex- linked dominant D. Sex- linked recessive

5 Weekly Vocabulary Allele noun different forms of the same gene. The allele for brown hair is B, while the allele for blonde hair is b. Autosomal adjective referring to an allele or gene NOT on a sex chromosome. Most of our traits are autosomal, since we have 22 pairs of chromosomes that are not sex chromosomes. Dihybrid adjective a cross looking at two traits at the same time. While eye color and hair color are independent of each other, we can predict the outcome of both at the same time using a dihybrid Punnett Square. Genotype noun the combination of alleles (genes) that an organism has for a trait (shown with two letters). We can have heterozygous or homozygous genotypes since the alleles are represented by letters. Monohybrid adjective a cross looking at one trait at a time. When we do a Punnett Square only looking at hair color, we are looking at a monohybrid cross. Multiple alleles noun a trait that has multiple variations. Some traits, such as blood type, have more than one allele and are known as multiple alleles. Pedigree noun a tool used to track traits through a family history. If you have a pure- bred dog, you probably have a pedigree for them as proof of their lineage. Phenotype noun the physical characteristics of an organism; the expression of the genes. While the genotype for hair color could be bb, the phenotype would be blonde hair. Punnett Square noun a tool used to predict the outcome of a certain genetic cross. We use Punnett Squres a lot in class when we re predicting genetic crosses! Sex- Linked adjective describing a trait on one of the sex chromosomes (usually the X chromosome). Hemophilia and color blindness are both sex- linked traits and therefore are much more common in males than in females.

6 Homework Wednesday January 23, 2013 These letters represent the genotypes of the rabbits: G- Grey hair g- white hair B- black eyes b- red eyes 1. Given the gametes (GB, Gb, GB, Gb) and (gb, gb, gb, gb), fill in the Punnett square: 2. A male rabbit with the genotype GgBb. Determine the gametes (sperm) produced by this rabbit. A female rabbit has the genotype ggbb. Determine the gametes (eggs) produced by this rabbit. Use the gametes from the male and female to set up a Punnett square below. How many of the offspring are gray with black eyes? How many of the offspring are gray with red eyes? How many of the offspring are white with black eyes? How many of the offspring are white with red eyes? 3. A male rabbit with the genotype GGbb is crossed with a female rabbit with the genotype ggbb. What are the possible gametes produced by the male?

7 What are the possible gametes produces by the female? Create and fill in a Punnett square for the possible offspring. How many of the offspring are gray with black eyes? How many of the offspring are gray with red eyes? How many of the offspring are white with black eyes? How many of the offspring are white with red eyes? 4. An aquatic arthropod called a Cyclops has antennae that are either smooth or barbed. The allele for barbs is dominant (B). In the same organism, resistance to pesticides is a recessive trait (r). A Cyclops that is resistant to pesticides and has smooth antennae is crossed with one that is heterozygous for both traits. Show the genotypes of the parents. x Set up a Punnett square for the cross.

8 Homework Thursday January 24, 2013 Imagine that the dark shapes are individual with a recessive disease. 1. Using the letter r, what would the genotype of someone with the disease have to be? On the diagram above, label all of the dark shapes with that genotype. 2. Using the letter R, what are the two genotypes someone with a white shape could have? 3. Label the genotypes of individuals I 1,II 2 and II 3. Remember that if someone has the disease, they had to get a recessive gene from both parents and that a parent with the disease has to pass on the recessive gene. 1. If you look at the offspring of the second line, you will notice that one of their kids is black. You can use this to tell if black is dominant or recessive. Using R/r, what is the genotype of black shapes? Label all of the black shapes in the diagram. 2. Now go back and label the genotypes of the parents in the second line. 3. Look at the middle parents in the third line and label their genotypes. How do you know their genotypes? Explain in two sentences below. On the question below, make sure you look for parents of the same color that produce a child that is an opposite color and label that child as being recessive before answering the question.

9 Since the polled allele is dominant, the horned allele has to be recessive. Write in the genotype of the recessive individuals BEFORE you do the problem. Use N/n

10 Ph.D. Extra Credit Summarize the following article for extra credit points. Privacy risk: researchers identify 'anonymous' DNA donors 21 January 2013 By Simon Hazelwood Appeared in BioNews 689 Anonymous genetic data posted on online resources may not be as secure as previously thought. A team of researchers in the USA has shown it is possible to link whole genome sequence data to a specific person, using only publicly available information. The technique, which is currently only able to identify males, uses genetic markers identified from whole genome sequences held anonymously in certain genetic research databases and matches it to information held in genealogy databases, which can be stored by surname. This gives a list of possible surnames, which may then be narrowed down to a specific person using demographic information made available in the genetic database and then cross referenced with other public information, potentially identifying the original anonymous contributor to the genetic research. Those with common surnames are less likely to be successfully identified. Using this technique, the group from the Whitehead Institute for Biomedical Research in Massachusetts was able to identify genomics entrepreneur Dr Craig Venter as well as several donors to genetic research databases, including the 1000 Genomes Project. Only males are able to be identified as the process works by analysing genetic markers known as Y- strs (Y- short tandem repeats) that are found on the male sex chromosome. As is common with surnames, DNA on the Y chromosome is passed from father to son. Genealogy databases can make use of this correlation and may openly store Y chromosome information by surname. In some cases, family members were also able to be identified. A person who submits their genetic information for research may reveal family genetic traits, which by using genealogy databases can be traced to identify other members in that family. While the accuracy rate is only around 12 percent, the discovery raises important questions on the security of genetic research. Dr Yaniv Erlich, who led the study, told the BBC: 'This is an important result that points out the potential for breaches of privacy in genomics studies'.

11 The authors have not published the names discovered nor the full details of the method used. The findings have been shared prior to publication with the US National Human Genome Research Institute, involved in the 1000 Genomes Project, which has since removed age information from its genome database. Speaking on the potential impact of the findings Dr Erlich said: 'We hope that this study will eventually result in better security algorithms, better policy guidelines, and better legislation to help mitigate some of the risks described'. The study was published in the journal Science. Summarize in your words: