Question 1

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

Accepted Answer

Alleles for each trait separate during gamete formation and unite at fertilization.

Question 2

In Mendel’s monohybrid cross between pure-breeding yellow peas (YY) and green peas (yy), what is the expected genotype ratio in the F2 generation?

Accepted Answer

$1:2:1$ (YY:Yy:yy)

Question 3

If a pea plant has the genotype Yy, what is the expected proportion of its gametes carrying the y allele?

Accepted Answer

$0.5$

Question 4

Which statement about alleles is correct according to Mendel’s findings?

Accepted Answer

Alleles are alternative forms of a gene, and an individual carries two copies for each trait.

Question 5

A dihybrid cross between two heterozygous pea plants (YyRr x YyRr) produces offspring with which phenotypic ratio?

Accepted Answer

$9:3:3:1$

Question 6

Which of the following is an example of a homozygous recessive genotype?

Accepted Answer

yy

Question 7

In Mendel’s experiments, what was the observed ratio of yellow to green peas in the F2 generation of a monohybrid cross?

Accepted Answer

$3:1$

Question 8

Which of the following best explains Mendel’s Law of Independent Assortment?

Accepted Answer

Alleles for different traits assort independently during gamete formation.

Question 9

If a plant with genotype Yy is self-fertilized, what is the probability that an offspring will be homozygous dominant?

Accepted Answer

$0.25$

Question 10

Which of the following is NOT a reason Mendel chose pea plants for his experiments?

Accepted Answer

Pea plants have only one form of each trait.

Question 11

A plant with genotype YyRr is crossed with a plant with genotype yyrr. What proportion of the offspring will have the genotype YyRr?

Accepted Answer

$0.25$

Question 12

Which term describes an individual with two different alleles for a trait?

Accepted Answer

Heterozygous

Question 13

In a dihybrid cross, which phenotype is expected to appear least frequently in the F2 generation?

Accepted Answer

Double recessive phenotype

Question 14

If two pea plants with genotype Yy are crossed, what is the expected frequency of heterozygous offspring?

Accepted Answer

$0.5$

Question 15

Which of the following best describes the genotype and phenotype relationship?

Accepted Answer

Genotype is the genetic makeup, phenotype is the observable trait.

Question 16

A plant with genotype YY is crossed with a plant with genotype yy. What will be the phenotype of all F1 offspring?

Accepted Answer

All yellow

Question 17

Which of the following is a key insight from Mendel’s experiments?

Accepted Answer

Inheritance is particulate, not blending.

Question 18

In a dihybrid cross, what is the probability of obtaining an offspring with both recessive traits (yyrr) from two YyRr parents?

Accepted Answer

$\frac{1}{16}$

Question 19

Which of the following scenarios demonstrates the concept of independent assortment?

Accepted Answer

A plant with genotype YyRr produces gametes with all possible combinations of Y/y and R/r alleles.

Question 20

If a heterozygous plant (Yy) is crossed with a homozygous recessive plant (yy), what is the expected ratio of yellow to green offspring?

Accepted Answer

$1:1$

Mendel’s Laws: Foundations of Classical Genetics

Study Guide - Practice Questions