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Answer the following questions based on the pedigree pictured above.
What is the genotype of each of the following: Homozygous individual: Heterozygous dominant individual: What is the phenotype of each of the following: What is the genotype of individual #1? Do individuals #4 and #5 have the same genotype?
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5. If individual #6 and his wife had 3 more children, what would be the probability that the children would be normal? 6. What is the probable genotype of individual #9? 7. List the phenotypes of these individuals: #3 #10 8. How many generations are represented?
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Incomplete dominance: In four o'clock flowers, red plants are homozygous for the allele (R) of the gene for flower color. Plants with white flowers are homozygous for the (r) allele of the same gene. Plants with pink flowers are heterozygous for these two alleles. Complete a Punnett square to show genotypes and phenotypes that are expected when plants with pink flowers are intercrossed. Codominance: In chickens, black feathers are codominant to white feathers. The heterozygous form is a checkered chicken. If a homozygous black male crosses with a heterozygous female, what are the genotypic and phenotypic ratios?
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Multiple Allele: 1. What crosses produce type A? 2. What crosses produce type B? 3. What crosses produce type AB? 4. What crosses produce type O?
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Dihybrid: If a pea plant that is heterozygous for round, yellow peas (RrYy) is crossed with a pea plant that is homozygous for round peas but heterozygous for yellow peas (RRYy), how many homozygous for round and green (yy) plants are possible?
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Dihybrid: If a pea plant that is heterozygous for round, yellow (RrYy) is crossed with a pea that is homozygous for round but heterozygous for yellow (RRYy), what is the probability of producing a pea that is … heterozygous for both traits? Homozygous dominant for both traits?
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Sex-linked Colorblindness is a sex-linked trait carried on the X chromosome. Cross a carrier female with a normal male. What is the probability of having: A color blind girl? A color blind boy?
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Sex-linked ****In fruit flies, eye color is a sex linked trait. Red is dominant to white **** What are the sexes and eye colors of flies with the following genotypes: X R X r X R Y X r X r X R X R X r Y Show the cross of a white eyed female X r X r with a red-eyed male X R Y Show a cross between a pure red eyed female and a white eyed male.
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Meiosis What is the purpose of meiosis?
What is the end result of meiosis? What type of cells are made during meiosis? Using the chart below which type of organism would have a sperm cell with 4 chromosomes?
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What is independent assortment?
When does it happen? If the sperm cell of a turtle contained 14 chromosomes, how many chromosomes would an egg cell of a turtle contain? How many would that of a newly formed zygote (baby turtle)?
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Karyotypes Is the karyotype of the right a male or female?
Is it normal or disordered? If disordered what disorder(s) does it have?
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Using the information sheet about non-disjunction disorders:
Describe the two disorders pictured on the karyotype. Be sure to note which chromosome causes the disorder.
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disorders Show up only in the homozygous recessive person (aa) who inherits a recessive allele from both parents, who were carriers (Aa xAa). (25% chance of this happening) 1. Cystic fibrosis: Homozygous recessives (cc) have cystic fibrosis - body cannot make needed chloride channel, high concentrations of extracellular chloride causes mucous to build up, infections, pneumonia. Diet, antibiotics and treatment can extend life to 25 years or more. 2. Tay-Sachs: Enzyme that breaks down brain lipids is non-functional in homozygous recessives (tt). Buildup of lipids causes death by age Sickle-cell disease: The most common inherited disease of African-Americans (1:400 affected). Homozygous recessives (ss) make abnormal form of hemoglobin that deforms red blood cells and causes a cascade of symptoms (clogging of blood vessels, organ damage, and kidney failure). 4. Achondroplasia (dwarfism): AA = Homozygous dominant is lethal - fatal (spontaneous abortion of fetus). Aa = dwarfism. aa = no dwarfism % of all people in the world are homozygous recessive (aa)..
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There is a mother who is a carrier for cystic fibrosis who has a child with a father who has cystic fibrosis. Draw a Punnett square for this combination. What are the chances of their children getting cystic fibrosis? Of not getting cystic fibrosis? 2. A father who is heterozygous (carrier) for Tay-Sachs disease marries and has kids. We do not know the genotype for his wife. They have 4 kids. Only one child has Tay-Sachs disease. What is the most likely genotype of the mother? Support your answer with a Punnett square. 3. A woman who is not a carrier for Sickle Cell Disease marries a male who is affected by the disease. They have a child. What are the chances of that child having the disease? Not having the disease? Support your answer using a Punnett square. 4. You have two parents that have achondroplasia who have a child who is of normal height (think Little Planet/Big World). Demonstrate, using a punnet square, how this type of offspring is possible with two affected parents
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Monohybrid Brown eyes (B) are dominant to blue eyes (b). If a brown eyed man who had a blue eye mother crosses with a blue eyed woman, what are the chances of having a… Homozygous Brown eyed child? Heterozygous brown eyed child? Homozygous blue eyed child?
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Tongue rolling is a dominant trait (R)
Tongue rolling is a dominant trait (R). What would be the expected tongue rolling ability of the children from a marriage between a non-rolling mother and a rolling father whose mother could not roll her tongue.
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