Genetics I Ch 11 - Take Home Quiz

1. Which of the statements below is/are true regarding the trait of interest in the above pedigree?
A. All of these statements are true.
B. If it is autosomal recessive, all the children of the affected daughter would be affected as well.
C. If it is X-linked dominant, the daughter of the affected son would also be affected.
D. It is likely autosomal dominant, the affected individuals would be heterozygous.
E. If it is X-linked recessive, all the children of the affected daughter would be affected.

2. According to the pedigree diagrammed above the original parents of this family tree had
A. 2 daughters and 1 son
B. None of these is correct
C. 3 daughters and 2 sons
D. 1 daughter and 2 sons
E. 2 daughters and 3 sons

3. A classical example of multiple alleles is
A. albinism in humans and animals.
B. pink flowers in heterozygous snapdragons.
C. ABO blood types in humans.
D. height in garden peas.
E. coat color spotting in cattle.

4. The water buttercup produces thin leaves underwater, but those same tissues will produce broad leaves above the water. Individuals in the 1800's (when hunger and childhood diseases were common) averaged slightly over five feet tall, but their offspring in the 1900's were substantially taller on the average. This reflects the influence of
A. gene linkage.
B. genotype having no relationship to phenotype.
C. epistasis.
D. environmental factors on the ability of genes to express themselves.
E. polygenic inheritance.

5. Which type of inheritance results in continuous variation often a bell-shaped curve–because genes at many loci are involved?
A. polygenic
B. autosomal dominant
C. sex-influenced
D. autosomal recessive
E. X-linked

6. If a human who is a tongue roller (T) and has unattached ear lobes (E) marries a person who cannot roll their tongue and has attached earlobes, could they produce an offspring that was also a non-tongue roller with attached earlobes? What would be the genotype of the first parent? the second parent?
A. yes: TTEe; ttee
B. yes; TtEe; ttee
C. unable to determine from the information given
D. yes; TtEE; ttEe
E. no; TTEE; ttee

7. The location on a chromosome where a particular gene is located is known as the:
A. diploid
B. allele
C. locus
D. autosome
E. dihybrid

8. In pea plants, the gene for round seed (R) is dominant, and wrinkled seeds (r) are recessive. The endosperm of the pea is also either starchy, a dominant gene (S), or waxy (s). What can be said of a fully heterozygous (or dihybrid) cross?
A. It is impossible to secure offspring that are homozygous for one dominant gene such as round seed and homozygous recessive for the other recessive waxy gene.
B. It is impossible to secure offspring that are homozygous for both dominant genes.
C. All of these choices are impossible combinations in a dihybrid cross.
D. It is impossible to secure offspring that are homozygous for both recessive genes.
E. All of these choices are possible combinations in a dihybrid cross.

9. A gene interaction in which a pair of recessive genes at one locus prevents expression of a dominant allele at another locus is called
A. epistasis.
B. polygenic inheritance.
C. pleiotropy.
D. complete dominance.
E. incomplete dominance.

10. An individual with blood type A marries an individual with blood type B. What blood types could their offspring exhibit?
A. AB
B. all of these are possible
C. A
D. B
E. O

11. The ability to roll the edges of the tongue upward in a U-shape has been considered to be an inherited ability. The standard assumption is that tongue-rolling is a dominant allele at a single gene locus. Which of the following would cast doubt on this assumption?
A. Behaviors are not inherited, only structures are inherited.
B. A student who can roll his tongue has a mother and father, both of whom cannot.
C. A student who cannot roll his tongue has a mother and father, both of whom can.
D. A teacher reports that after testing her class on the ability to roll their tongue, with very little effort the non-tongue-rollers can learn to also roll their tongues.
E. The non-tongue rollers who learn to roll their tongues and the student who can roll his tongue while his parents cannot are two situations that cast doubt on the heritability issue. The situation where a student cannot roll his tongue while his parents can is inconclusive.

12. A classical example of incomplete dominance is
A. coat color in rabbits.
B. height in garden peas.
C. albinism in humans and animals.
D. pink flowers in heterozygous snapdragons.
E. ABO blood groups in humans.

13. If an individual with a dominant phenotype is crossed with an individual with a recessive phenotype, 4 of their 9 offspring show the recessive phenotype. What is the genotype of the first parent?
A. AA
B. Aa
C. The answer cannot be determined from this information.
D. aa
E. AA or Aa

14. The F2 offspring of a monohybrid cross would show the genotype(s)
A. Aa and aa.
B. AA and Aa.
C. AA only.
D. Aa only.
E. AA, Aa, and aa.

15. In which kind of cross would you expect to find a ratio of 9:3:3:1 among the F2 offspring?
A. monohybrid cross
B. dihybrid cross
C. multiple allele cross
D. testcross
E. polygenic cross

16. If you had two guinea pigs of opposite sex, both homozygous, one black and one brown, but you didn't know which was the dominant characteristic, how would you find out the dominant color?
A. None of the choices are correct.
B. Mate them together, then mate their offspring to see what color the grandchildren are--the other color will be the dominant color.
C. Mate them together , then mate their offspring to see what color the grandchildren are--that will be the dominant color.
D. Mate them together and see what color the offspring are--that will be the dominant color.
E. Mate them together and see what color the offspring are--the other will be the dominant color.

17. In a pedigree chart, which is correct?
A. Offspring are represented by triangles.
B. All of these are true.
C. A line between a circle and a square represents a mating.
D. A carrier with a normal phenotype is represented by a black circle or square.
E. Circles = males; squares = females.

18. Which of the following crosses would always result in offspring that only display the dominant phenotype?
A. Tt x Tt
B. TT x TT
C. both TT x tt and TT x TT
D. TT x tt
E. Tt x Tt

19. In the use of a Punnett square for genetic results of crossing individuals
A. All of the choices are correct.
B. the results show the offspring's expected genotypes.
C. all different kinds of eggs are lined up either horizontally or vertically.
D. all different kinds of sperm are lined up either horizontally or vertically.
E. every possible allele combination is placed within the square.

20. Following the type of inheritance illustrated in this pedigree, if one of the affected children (who is heterozygous) in the second generation were to marry an unaffected spouse, what is the probability their first child will be affected?
A. 100%
B. Not enough information to tell.
C. 1 out of 4
D. 3 out of 4
E. 1 out of 2