Question 1

Which of the following best describes Mendel's principle of segregation?

Accepted Answer

Each parent contributes only one allele for each gene to their offspring, and these alleles separate during gamete formation.

Question 2

A cross between two heterozygous pea plants (Pp x Pp) for flower color results in what phenotypic ratio in the offspring?

Accepted Answer

$$3:1$$

Question 3

Which of the following is an example of incomplete dominance?

Accepted Answer

A cross between red and white four-o'clock flowers produces pink flowers in the F1 generation.

Question 4

In a dihybrid cross between two heterozygous plants (YyRr x YyRr), what is the probability of obtaining an offspring with the genotype yyrr?

Accepted Answer

$$\frac{1}{16}$$

Question 5

Which of the following statements about dominant alleles is correct?

Accepted Answer

Dominant alleles are not necessarily more common or better adapted than recessive alleles.

Question 6

A woman with normal vision has a son who is red-green colorblind. Which of the following must be true?

Accepted Answer

She is a carrier for the red-green colorblindness allele.

Question 7

Which of the following best explains why individuals with type O blood are considered universal donors?

Accepted Answer

Their red blood cells lack A and B antigens, so they do not trigger an immune response in recipients.

Question 8

A testcross is performed to determine the genotype of a pea plant with a dominant phenotype. Which of the following crosses would you use?

Accepted Answer

Cross the plant with a homozygous recessive individual.

Question 9

Which of the following is an example of pleiotropy?

Accepted Answer

A single gene mutation causes both sickle cell anemia and resistance to malaria.

Question 10

If a trait is polygenic, which of the following is most likely true?

Accepted Answer

The trait shows continuous variation in the population.

Question 11

Which of the following best describes codominance?

Accepted Answer

Both alleles are fully expressed in the phenotype of a heterozygote.

Question 12

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

Accepted Answer

Type A or Type B

Question 13

Which of the following is a key feature of X-linked recessive inheritance?

Accepted Answer

More males than females are affected.

Question 14

In a cross between KkLlMm x KkLlMm, what fraction of the offspring will be homozygous recessive for all three genes (kkllmm)?

Accepted Answer

$$\frac{1}{64}$$

Question 15

Which of the following is an example of gene-by-environment interaction?

Accepted Answer

A plant's flower color varies depending on soil pH.

Question 16

Which of the following is true about mitochondrial inheritance?

Accepted Answer

Traits are inherited only from the mother.

Question 17

Which of the following best describes the difference between autosomal dominant and autosomal recessive inheritance?

Accepted Answer

Autosomal dominant traits appear in every generation, while autosomal recessive traits often skip generations.

Question 18

Which of the following is a likely outcome of a transfusion reaction between a type A patient and a type B donor?

Accepted Answer

Agglutination and hemolysis of the donor red blood cells.

Question 19

Which of the following is a multifactorial trait?

Accepted Answer

Human intelligence, which is influenced by both genes and environment.

Question 20

Which of the following best explains why Mendel did not observe polygenic inheritance in his pea plant experiments?

Accepted Answer

He used true-breeding lines that were homozygous for nearly all traits except the one in question.

Chapter 14: Mendelian Genetics and Extensions

Study Guide - Practice Questions