Chapter 15 practice Questions AP Biology- Aquinas High …

Chapter 15 practice Questions AP Biology

1) What does a frequency of recombination of 50% indicate? A) The two genes likely are located on different chromosomes.

B) All of the offspring have combinations of traits that match one of the two parents. C) The genes are located on sex chromosomes. D) Abnormal meiosis has occurred. E) Independent assortment is hindered.

2) A 0.1% frequency of recombination is observed A) only in sex chromosomes.

B) only on genetic maps of viral chromosomes. C) on unlinked chromosomes.

D) in any two genes on different chromosomes.

E) in genes located very close to one another on the same chromosome.

3) The frequency of crossing over between any two linked genes is A) higher if they are recessive.

B) different between males and females. C) determined by their relative dominance. D) the same as if they were not linked.

E) proportional to the distance between them.

4) Males are more often affected by sex-linked traits than females because A) males are hemizygous for the X chromosome.

B) male hormones such as testosterone often exacerbate the effects of mutations on the X chromosome. C) female hormones such as estrogen often compensate for the effects of mutations on the X. D) X chromosomes in males generally have more mutations than X chromosomes in females. E) mutations on the Y chromosome often exacerbate the effects of X-linked mutations.

Use the list of chromosomal systems below to answer the following questions. A. haploid-diploid B. X-0 C. X-X D. X-Y E. Z-W

5) What is the chromosomal system for determining sex in mammals?

6) What is the chromosomal system for sex determination in grasshoppers and certain other insects?

7) What is the chromosomal system for sex determination in birds?

8) What is the chromosomal system of sex determination in most species of ants and bees? Answer: A

9) Red-green color blindness is a sex-linked recessive trait in humans. Two people with normal color vision have a color-blind son. What are the genotypes of the parents? A) XcXc and XcY B) XcXc and XCY C) XCXC and XcY D) XCXC and XCY E) XCXc and XCY

10) Cinnabar eyes is a sex-linked recessive characteristic in fruit flies. If a female having cinnabar eyes is crossed with a wild-type male, what percentage of the F1 males will have cinnabar eyes? A) 0% B) 25% C) 50% D) 75% E) 100%

Refer to the following information to answer the questions below.

An achondroplastic male dwarf with normal vision marries a color-blind woman of normal height. The man's father was six-feet tall, and both the woman's parents were of average height. Achondroplastic dwarfism is autosomal dominant, and red-green color blindness is X-linked recessive.

11) How many of their daughters might be expected to be color-blind dwarfs? A) all B) none C) half

D) one out of four E) three out of four

12) How many of their sons would be color-blind and of normal height? A) all B) none C) half

D) one out of four E) three out of four

13) They have a daughter who is a dwarf with normal color vision. What is the probability that she is heterozygous for both genes? A) 0 B) 0.25 C) 0.50 D) 0.75 E) 1.00

14) Of the following human trisomies, the one that generally has the most severe impact on the health of the individual is A) trisomy 21.

B) Klinefelter syndrome (XXY). C) trisomy X. D) XYY.

E) All of the above have equal impact.

15) What do all human males inherit from their mother? A) mitochondrial DNA B) an X chromosome C) the SRY gene D) A and B only E) A, B, and C

Answers: 1A, 2E, 3E, 4A, 5D, 6B, 7E, 8A, 9E, 10E , 11B, 12C, 13E, 14A, 15D