Name ______Date ______Hour ______

Genetics Test Study Guide

Define the following vocabulary words:

  1. Punnett Square (p. 182) –
  2. Heredity (p. 173) -
  3. Gregor Mendel (p. 173) –
  4. Alleles (p. 178) –
  5. Dominant (p. 177) –
  6. Recessive (p. 177)–
  7. Genotype (p. 180) –
  8. Phenotype (p. 180) –
  9. Heterozygous (p. 181) –
  10. Incomplete Dominance (p. 184)–
  11. Codominance (p. 184)–
  12. Sex-Linked Traits (p. 237)–
  13. Polygenic Traits (p. 242) –
  1. Can a mother and father with brown eyes have a child with blue eyes? Create a Punnett Square as proof that this is possible and explain your answer.
  1. Explain the difference between homozygous dominant, homozygous recessive and heterozygous. Give an example of each. (p. 181)
  1. Explain the difference between chromosome and gene mutations. Give an example of each. (p. 239-240)
  1. In humans, having freckles (F) is dominant over not having freckles (f). Cross a girl and boy who are both heterozygous for freckles. List the genotype and phenotype percentages.
  1. From the cross in #17, what is the probability their children would have freckles? Would NOT have freckles?
  1. Cross a homozygous recessive individual with a heterozygous individual using the letter B. List the genotype percentages from the cross.
  2. Tallness (T) is dominant over shortness (t) in pea plants. How would you write the genotype of a plant that is heterozygous for tallness?
  1. In rabbits, black fur (B) is dominant over brown fur (b). Cross a homozygous dominant rabbit with a homozygous recessive rabbit. List the genotype and phenotype percentages.
  1. What fur color would a homozygous dominant rabbit have?
  1. What fur color would a homozygous recessive rabbit have?
  1. If the trait for coat color in cows is codominant, what color would offspring cows be if their parents are a red cow and a white cow?
  1. What kind of traits determine skin color? (p. 242 near the bottom)
  1. A mother is heterozygous for blood type A and the father is heterozygous for blood type B. What is the probability that their child will be blood type O? Show the cross.
  1. The genes for hemophilia are located on the X chromosome. It is a recessive disorder in which the blood does not clot. The mother is a carrier for hemophilia and the father is normal for blood clotting. What is the probability that a son will have hemophilia?
  1. Within the skin cells of a child, a mutation occurs that causes skin cancer. Who will this mutation affect?
  1. What is nondisjunction? How can it cause Down syndrome? Explain.
  1. If a red flower and white flower are crossed to make pink flowers, what is this an example of?
  1. Using the letter B, write the genotype for a heterozygous organism.