Question 1

Which of the following best describes Mendel’s Principle of Segregation?

Accepted Answer

Pairs of alleles are separated during meiosis I in the formation of gametes.

Question 2

A pea plant with genotype RrYy is self-fertilized. What is the probability that an offspring will have wrinkled, green seeds? (R = round, r = wrinkled; Y = yellow, y = green)

Accepted Answer

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

Question 3

In Mendel’s monohybrid cross between true-breeding round-seeded (RR) and wrinkled-seeded (rr) pea plants, what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

3:1

Question 4

Which of the following statements about alleles is correct?

Accepted Answer

Alleles are different forms of a gene that may produce different phenotypes.

Question 5

A test cross is performed between a pea plant with an unknown genotype for seed shape (dominant phenotype) and a homozygous recessive plant. If all offspring have round seeds, what is the genotype of the unknown parent?

Accepted Answer

Homozygous dominant (RR)

Question 6

Which of the following is NOT a reason why Mendel chose Pisum sativum (pea plants) as his model organism?

Accepted Answer

They have a long generation time.

Question 7

If a plant is heterozygous for two traits (RrYy), what proportion of its gametes will be rY according to the principle of independent assortment?

Accepted Answer

$$\frac{1}{4}$$

Question 8

Which of the following best explains why the wrinkled seed phenotype disappeared in the F1 generation but reappeared in the F2 generation in Mendel’s experiments?

Accepted Answer

The wrinkled allele is recessive and masked by the dominant round allele in heterozygotes.

Question 9

A dihybrid cross between two heterozygous pea plants (RrYy x RrYy) produces which phenotypic ratio in the F2 generation?

Accepted Answer

9:3:3:1

Question 10

Which of the following is an example of a polymorphic trait in pea plants?

Accepted Answer

Flower color that appears as either purple or white

Question 11

If a pea plant with genotype Rr is crossed with another Rr plant, what is the probability that an offspring will be homozygous recessive?

Accepted Answer

$$\frac{1}{4}$$

Question 12

Which of the following best describes a true-breeding (pure line) individual?

Accepted Answer

An individual that only produces progeny with the same phenotype over many generations

Question 13

Which of the following is a correct statement about the genotype and phenotype relationship?

Accepted Answer

The phenotype is the observable manifestation of the genotype.

Question 14

In a cross between a homozygous dominant (RR) and a homozygous recessive (rr) pea plant, what will be the genotype of all F1 offspring?

Accepted Answer

Rr

Question 15

Which of the following is NOT a feature of Mendel’s experimental approach that contributed to his success?

Accepted Answer

He relied on blending inheritance as his main hypothesis.

Question 16

If a plant with genotype RrYy produces gametes, what is the expected proportion of gametes with the genotype rY?

Accepted Answer

$$\frac{1}{4}$$

Question 17

Which of the following best explains the principle of independent assortment?

Accepted Answer

Alleles of different genes are transmitted independently of each other during gamete formation.

Question 18

A plant with genotype RrYy is crossed with a plant with genotype rryy. What proportion of the offspring will have round, yellow seeds?

Accepted Answer

$$\frac{1}{4}$$

Mendel and the Gene: Mono-, Di-, and Trihybrid Crosses

Study Guide - Practice Questions

Study Guide - Flashcards