Question 1

Which of the following best describes the principle of independent assortment in genetics?

Accepted Answer

Alleles of different genes segregate independently of one another during gamete formation.

Question 2

A geneticist is studying two linked genes, A and B, located 10 map units apart. What is the expected recombination frequency between these genes?

Accepted Answer

$$10\%$$

Question 3

In a dihybrid cross between two heterozygous individuals ($$AaBb 	imes AaBb$$), what is the expected phenotypic ratio in the offspring, assuming independent assortment?

Accepted Answer

$$9:3:3:1$$

Question 4

A pedigree shows a trait that appears in every generation and affects both males and females equally. What is the most likely mode of inheritance?

Accepted Answer

Autosomal dominant

Question 5

If a woman who is a carrier for cystic fibrosis ($$Ff) $$and a man who is homozygous normal ($$FF) $$have a child, what is the probability that the child will be a carrier?

Accepted Answer

$$0.5$$

Question 6

Which equation correctly represents the Hardy-Weinberg equilibrium for a gene with two alleles, $$A$$ and $$a$$, with frequencies $$p$$ and $$q$$?

Accepted Answer

$$p^2 + 2pq$$ + $$q^2 = 1$

Question 7

A test cross is performed between a plant with genotype $$AaBb$$ and a plant with genotype $$aabb. If $$the genes are unlinked, what proportion of the offspring will have the genotype $$AaBb$$?

Accepted Answer

$$0.25$$

Question 8

A couple has a child with sickle cell anemia, an autosomal recessive disorder. Neither parent shows symptoms. What are the genotypes of the parents?

Accepted Answer

Both are heterozygous carriers ($$Ss)$$

Question 9

Which of the following scenarios best illustrates genetic linkage?

Accepted Answer

Two genes located close together on the same chromosome are inherited together more often than not.

Question 10

A population of 1000 individuals has 360 with genotype $$AA$$, 480 with genotype $$Aa$$, and 160 with genotype $$aa. $$What is the frequency of allele $$A$$?

Accepted Answer

$$0.6$$

Question 11

Which of the following is a real-world example of incomplete dominance?

Accepted Answer

The pink flower color in snapdragons resulting from crossing red and white flowers.

Question 12

A man with blood type AB marries a woman with blood type O. What are the possible blood types of their children?

Accepted Answer

A and B only

Question 13

Which of the following best explains the concept of penetrance in genetics?

Accepted Answer

The proportion of individuals with a particular genotype who actually express the associated phenotype.

Question 14

If two genes show a recombination frequency of $$20\%$$, what does this indicate about their physical relationship?

Accepted Answer

They are located 20 map units apart on the same chromosome.

Question 15

A woman who is heterozygous for an X-linked recessive disorder marries a man who does not have the disorder. What is the probability that their son will have the disorder?

Accepted Answer

$$0.5$$

Question 16

Which of the following is the best definition of epistasis?

Accepted Answer

One gene masks or modifies the expression of another gene.

Question 17

In a population in Hardy-Weinberg equilibrium, if the frequency of allele $$a is$$ $$0.3$$, what is the expected frequency of heterozygotes ($$Aa$$)?

Accepted Answer

$$0.42$$

Question 18

A geneticist observes that two genes have a recombination frequency of $$50\%. $$What does this suggest about their location?

Accepted Answer

They are either on different chromosomes or far apart on the same chromosome.

Question 19

Which of the following is a consequence of genetic drift in a small population?

Accepted Answer

Random changes in allele frequencies that can lead to loss of genetic variation.

Question 20

A woman with genotype $$Bb$$ for a gene with complete dominance marries a man with genotype $$bb. $$What is the probability that their child will express the dominant phenotype?

Accepted Answer

$$0.5$$

Genetics Exam Syllabus and Format Overview

Study Guide - Practice Questions

Study Guide - Flashcards