1. What does it mean to perform a dihybrid cross?
2. Crossing two pink snapdragons yields some seeds that produce red-flowering plant, some seeds that produce white-flowering plants and some seeds that produce pink-flowering plants. If this trait operates by incomplete dominance and the allele R represents red flowers and the allele r represents white flowers, what genotype would a plant with pink flowers have for this trait?
3. What is nondisjunction?
4. What is the connection between sickle-cell anemia and malaria?
5. What do hemophilia, Duchenne muscular dystrophy, and red-green color blindness have in common?
6. Match the following
7. Red-green color blindness is an X-linked recessive trait in humans. A color-blind woman and a man with normal is the probability that the son is color blind?
8. If an individual has genotype AaBb, how many difference gametes can he or she produce? What combinations of alleles are possible?
9. A man with type AB blood produces offspring with a female that has a type A blood. What type blood would it not be possible for the offspring to have?
10. A person who is heterozygous for the Huntington’s disease (HD) allele has offspring with someone who does not have D. What proportion of their children will have HD?
11. In Mendel’s pea plant, yellow seeds are dominant to green seeds. If a true-breeding green-seed-producing plant is crossed to a heterozygous yellow-seed-producing plant, what percentage of offspring produces green seeds?
12. In humans, “unattached” earlobes are dominant over “attached” earlobes. Widow’s-peak hairline is dominant over non-widow’s-peak hairline. Use E and e for the earlobe phenotype alleles and W and w for the hairline phenotype alleles. A woman with unattached earlobes and a widow’s peak and a man with attached earlobes and a widow’s peak have a child. The child has attached earlobes and a non-widow’s-peak hairline. What are the genotypes of the parents?
13. A woman is missing one of her X chromosomes. With what conditions, would she be diagnosed?
14. In science, success is often determined by whether the right organism is used for research. What organism did Mendel use to learn more about genetics? Explain why “this” was the perfect organism?Your essay should be at least 200 words in length and include an introduction, a body, and a conclusion.
