Offspring have similar physical characteristics, or traits, as their parents because genetic information (DNA) is passed from parent to offspring

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3 7.L.4A.1 Obtain and communicate information about the relationship between genes and chromosomes to construct explanations of their relationship with inherited characteristics

4 Offspring have similar physical characteristics, or traits, as their parents because genetic information (DNA) is passed from parent to offspring during sexual reproduction.

5 Inherited Traits Dad gives baby 23 chromosomes Mom gives baby 23 chromosomes 46 chromosomes (23 pairs)

6 Each sex cell (egg or sperm) of the parent organism (plant or animal) contains one-half of the genetic material needed to create a new organism.

7 HEREDITY passing of traits from one generation to another Remember: Offspring (can be a plant or animal) receive half of their DNA from EACH parent during reproduction

8 This is why humans have some features that are like their mom s side of the family and some that are like their dad s side of the family

9 DNA (deoxyribonucleic acid) Set of instructions for a living organism During sexual reproduction, half of the mom s DNA is in the egg and half of the dad s DNA is in sperm When egg and sperm combine, the organism will have a full set of DNA.

10 Genetic information is coded in DNA DNA is found in the nucleus of plant and animal cells. In order to fit in the nucleus, it coils to form a double helix, which looks like a spiral/twisted ladder.

11 DNA is composed of 4 nitrogenous base pairs and a phosphorous and sugar backbone. Nitrogenous base pairs are adenine, thymine, cytosine, and guanine. Adenine always pairs with thymine & cytosine always pairs with guanine Apples in the Tree Cars in the Garage

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13 RNA (ribonucleic acid) is a single strand of nitrogenous base pairs with a phosphorous and sugar backbone. RNA is used by the cell to aid the process of DNA transcription and translation. Why RNA is just as cool as DNA!

14 What is transcription and translation? Transcription and translation are processes used to make proteins within a cell. It is happening right now in most of the cells in your body. Extention video

15 Chromosomes are a structure found in the nucleus of a cell that contains the genetic information (DNA). Chromosomes are composed of long strands of DNA

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17 Chromosomes are made of long strands of DNA. Humans have 46 chromosomes. How many come from mom? How many from dad?

18 What makes you have certain characteristics from your parents? Your Genes! No not the ones you wear but the ones that are on your chromosomes. Are genes responsible for acquired traits (learned) or inherited traits? Inherited traits because you get them from your parents!

19 Genes are segments of DNA found on a chromosome that contribute to the inheritance of a certain trait. Genes come in pairs on a chromosome. One gene from a pair is called an allele. One allele came from mom s DNA and the other allele came from dad s DNA.

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22 Describing an organism based on its genes is called its genotype. Capital and lowercase letters are used to represent genotypes. For example, describing a pea plant as Tt, TT, or tt.

23 Describing an organism based on how the genes express themselves to make the organism look a certain way is called its phenotype. photo For example, describing a pea plant as tall, short, round or wrinkled.

24 Stop and think Which of the following is an example of a genotype? a. Brown hair b. Bb Which of the following is an example of a phenotype? a. Freckles b. FF

25 Describe how traits, in the form of genetic information, are transferred from parent to offspring. In your response, you must accurately use the terms gene, chromosome, and DNA.

26 7.L.4A.2 Construct explanations for how genetic information is transferred from parent to offspring in organisms that reproduce sexually.

27 Journal 11/14/16 How is genetic information passed from parents to offspring? Use ALL of the following words in your answer. Chromosome, gene, allele, DNA, nucleus, cell Want a challenge??? Use these Bonus words! Recessive & Dominant traits

28 How is genetic information passed from parents to offspring? 23 chromosomes come from the dad (sperm cell) and 23 chromosomes come from the mom (egg cell). Chromosomes are made up of long strands of DNA. Chromosomes are found in the nucleus of every cell. There are 46 Chromosomes or 23 pairs in EVERY cell. Genes are found in pairs on chromosomes. Genes tell us what traits an organism will have. One gene is called an allele. Every trait is either dominant or recessive.

29 TRAIT characteristic INHERITED TRAIT passed from parent to offspring through DNA Born with it ACQUIRED TRAIT something you learn or that you get from the environment while living your life

30 Which traits are inherited and which are acquired? Hair color Eye color Sickness from pollution Facial features Injury to body from accident Body frame Skin color Learning to play an instrument

31 The inherited traits of the offspring all depend upon the alleles that it gets from its parents. Some alleles are dominant and other alleles are recessive. Dominant describes a trait that covers over, or dominates, another form of that trait Recessive describes a trait that is covered over, or dominated, by another form of that trait and it seems to disappear.

32 The dominant allele will be expressed (or show up in the physical characteristics) no matter what other alleles are present. Dominant alleles are represented by CAPITAL LETTERS. Recessive alleles are represented by lowercase letters.

33 The recessive allele will only be expressed if two recessive alleles are present. If a dominant allele is present, the recessive trait will not be expressed. It will be hidden or masked over by the dominant trait. IF THE BIG LETTER COMES OUT TO PLAY, THE LITTLE LETTER RUNS AND HIDES AWAY An example: the tongue rolling dominant gene

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44 7.L.4A.3 Develop and use models (Punnett squares) to describe and predict patterns of the inheritance of single genetic traits from parents to offspring (including dominant and recessive traits, incomplete dominance, and codominance) 7.L.4A.4 Use mathematical and computational thinking to predict the probability of phenotypes and genotypes based on patterns of inheritance

45 Punnett Square A Punnett square is a tool used to determine possible offspring genotypes and phenotypes Diagram showing the gene combinations that might result from a genetic cross Used to calculate the probability of inheriting a particular trait Probability - the chance that a given event will occur

46 Monohybrid Crosses In a Punnett square for a monohybrid cross, the probability of only one trait is being determined Each square in the Punnett square represents a 25% chance

47 Monohybrid Crosses Monohybrid crosses only determine the probability of ONE gene It is difficult to predict most traits in humans because there are multiple genes that control these traits. Polygenic traits are those traits that are controlled by more than one gene. Such traits may even be controlled by genes located on entirely different chromosomes. Ex: human height, eye and hair color, and skin color

48 Monohybrid Crosses In a Punnett square, the top of the table shows the alleles provided by one parent. The alleles for the other parent are placed along the left side of the table. Parent one Parent two

49 Monohybrid Crosses One allele from each parent is placed in the individual squares, forming a new gene pair. The individual squares show the possibilities of allele pairs in the offspring. Offspring

50 What is a gamete? A gamete is a cell that fuses with another cell during fertilization. sperm and egg v=i-0rsv6oxsy

51 Let s Try it Together!

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55 You Try it Now!

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59 Beyond Dominant & Recessive Alleles Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes.

60 Incomplete Dominance Blending Incomplete dominance is a condition when there is more than one dominant allele. As a result, both alleles will be expressed in the phenotype. An example of incomplete dominance in plants may be flower color. The color red is dominant over the recessive color white. Pink flowers are a result of a blending of red and white.

61 Incomplete Dominance Blending Incomplete dominance is when one allele is not completely dominant over another Since one allele is not completely dominant over the other allele, we use two different capital letters to represent the alleles

62 Incomplete Dominance An example of incomplete dominance in plants may be flower color. The color red is dominant over the recessive color white. Pink flowers are a result of a blending of red and white.

63 Co-Dominance Pattern Co-dominance is a condition when there is more than one dominant allele. As a result, both alleles will be expressed in the phenotype. An example of co-dominance may be flower color. If both red and white alleles are dominant, both traits will be expressed in the flower usually in a random spotted pattern. Blood type in humans is another example of co-dominance.

64 Co-Dominance Pattern Codominance - both alleles contribute to the phenotype Since one allele is not completely dominant over the other allele, and both traits appear together, we use two different capital letters to represent the alleles

65 Co-Dominance Both alleles of a gene contribute to the phenotype of the organism Example: A solid white cow is crossed with a solid brown cow and the resulting offspring are spotted brown and white (called roan)

66 st Let s do the 1 one together Birds can be blue, white, or white with blue-tipped feathers 1. Incomplete Dominance or Codominance? 2. Genotypes: bluewhite blue-tipped 3. Show a cross between a white and blue-tipped bird

67 Practice Identifying A cat can be black, tan, or tabby (black & tan) 1. Incomplete Dominance or Codominance? 2. Genotypes: blacktan tabby 3. Show a cross between a heterozygous tabby and tan cat

68 Practice Identifying A sneech can be tall, short, or medium 1. Incomplete Dominance or Codominance? 2. Genotypes: tallshort medium 3. Show a cross between two heterozygous sneeches

69 Practice Identifying A horse can be black, white, or roan (black & white) 1. Incomplete Dominance or Codominance? 2. Genotypes: black white roan 3. Show a cross between a heterozygous roan and black horse

70 Practice Identifying Flowers can be white, pink, or red 1. Incomplete Dominance or Codominance? 2. Genotypes: whitepink red3. Show a cross between a white and red flower

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72 7.L.4A.5 Construct scientific arguments using evidence to support claims for how changes in genes (mutations) may have beneficial, harmful, or neutral effects on organisms

73 Genetic Mutations A mutation is any change in the genes of an organism. There are many causes for mutations. Many mutations occur randomly where others can be the result of some environmental exposure.

74 Genetic Mutations Chemicals, ultraviolet rays, and radiation can damage genes. However, most mutations occur when the cell makes errors as it copies its genes. Genes are made out of DNA, a chemical code with four different 'letters'. Each time one of your cells divides, it must copy around 6000 million letters of DNA code. Occasionally, mistakes are made, causing mutations. Most of these are corrected immediately, but a few manage to escape unnoticed.

75 Genetic Mutations Most mutations are automatically repaired by the organism s enzymes and therefore have no effect. When the mutation is not repaired, the resulting altered chromosome or gene structure is then passed to all subsequent daughter cells of the mutant cell, which may have adverse or beneficial effects on the cell, the organism, and future generations.

76 Genetic Mutations If the mutant cell is a body cell (somatic cell), the daughter cells can be affected by the altered DNA, but the mutation will not be passed to the offspring of the organism. Body cell mutations can contribute to the aging process or the development of many types of cancer

77 Genetic Mutations If the mutant cell is a gamete (sex cell), the altered DNA will be transmitted to the embryo and will be passed to subsequent generations. Gamete cell mutations can result in genetic disorders.

78 Genetic Mutations Mutations can have a beneficial, harmful, or neutral effect on the organism. Some mutations could be classified as both beneficial and harmful.

79 Beneficial Mutations Example of beneficial mutations: High cholesterol is associated with heart disease and is why people should limit eating high cholesterol foods, such as fried chicken and bacon. But there are some people who are born with a genetic mutation that allows them to eat any food they want and their cholesterol levels remain low. They have 90% reduced risk of heart disease.

80 Genetic Mutations Example of beneficial mutations: People who are native to cold climates have at least a partial genetic component to adapting to their way of life. They have higher rates of metabolism, maintain their body temperature better without shivering, and have fewer sweat glands on their bodies but more on their faces.

81 Genetic Mutations In some cases mutations are beneficial to organisms. Beneficial mutations are changes that may be useful to organisms in different or changing environments. These mutations result in phenotypes that are favored by natural selection and increase in a population

82 Genetic Mutations Example of harmful mutations: Sometimes a mutation can affect a gene known as p53. This gene makes a protein that stops mutated cells from dividing. But if p53 itself becomes mutated, the cell can start dividing uncontrollably and it can result in tumors and cancer. More than 50% of all cancers involve a mutated p53 gene and are almost always acquired (not inherited) mutations.

83 Genetic Mutations Example of harmful mutations: Cystic Fibrosis Some people inherit two copies of a mutated CFTR gene from their parents, which causes cystic fibrosis. Cystic fibrosis is a disease characterized by the buildup of thick, sticky mucus that can damage many of the body s organs. Mucus should be a watery substance

84 Genetic Mutations Example of harmful mutations: Tay-Sachs disease Tay-Sachs disease is caused by a genetic mutation. It is recessive so must have two copies for the disease to show up. It affects the nervous system and can cause deafness, blindness, loss of muscle function, slow growth and is fatal. It can also have delayed onset in adults but is extremely rare.

85 Genetic Mutations Example of a mutation that is beneficial and harmful: In some people, there is a mutation in a gene that makes hemoglobin in red blood cells. If a person inherits one copy of the mutated gene, it helps protect them from a disease called malaria. But if a person inherits two copies of the mutated gene, they will have a disease called sickle cell anemia, which causes red blood cells to change to a crescent shape and can clog capillaries.

86 Types of Mutations Mutations are changes in the sequence of DNA and can occur in many ways. Deletion - when DNA is removed or deleted. This can be as small as one base pair or as large as a section of chromosome.

87 Types of Mutations Insertions - when DNA is inserted or added into another section of DNA. As in a deletion, insertions can occur as a single base pair or large sections of chromosome.

88 Types of Mutations Frameshift - an insertion or deletion that is not in a multiple of three. This causes an entire shift of the reading frame and therefore the amino acid sequence is not properly assembled. This typically results in non-functional or dysfunctional proteins.

89 Types of Mutations Translocation - when large chunks of DNA is swapped between non-homologous chromosomes.

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91 7.L.4A.6 Construct scientific arguments using evidence to support claims concerning the advantages and disadvantages of the use of technology (such as selective breeding, genetic engineering, or biomedical research) in influencing the transfer of genetic information

92 Genetic Engineering Genetic engineering is the manipulation of an organism s genes. There are many types of genetic engineering.

93 Selective Breeding Process used to breed or reinforce desired traits into a particular organism. The breeder purposely chooses two organisms with a desired quality and has them mate to that they have offspring with the desired quality.

94 Selective Breeding For example, one of the oldest examples of selective breeding is the diversity within dogs. The species has changed dramatically from its wolf ancestors Used to reinforce certain desired traits such as herding behaviors, body shape, and fur type

95 Selective Breeding Advantages of Selective Breeding: Free process that can be used to breed plants or animals Has resulted in high yielding crops that are resistant to pests and disease

96 Selective Breeding Disadvantages of Selective Breeding: Selectively bred animals sometimes have higher risks for diseases Reduced genetic diversity, which lessens the chances of survival of a population in changing environmental circumstances

97 Genetically Modified Organisms Technology: Can be used to add or modify genes directly in the DNA of living things. These genetically modified organisms (GMOs) can be used in food or in other ways.

98 Genetically Modified Organisms GMO: For example, resistance to plant diseases can be added to a corn s DNA so the plant is not affected by these diseases

99 Genetically Modified Organisms Advantages to GMOs: Better for environment because don t need chemical pesticides and fertilizers Resistant to diseases Increased nutrition

100 Genetically Modified Organisms Disadvantages to GMOs: Pollen from GMOs can escape into the wild, which would be bad for genetic diversity GMOs can be dangerous to some insects

101 Key areas of controversy: Labeling Role of government Effect of GMOs on health and environment Effect of pesticide resistance

102 Biomedical Research Biomedical Research: Employs a variety of techniques to advance medical science and improve human lives. For example, the human genome project has mapped the entire human genome. This information can be used to inform individuals during genetic counseling and when making health decisions