Question 1

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

Accepted Answer

Each organism inherits two alleles for each gene, one from each parent, and these alleles separate during gamete formation.

Question 2

In a testcross between a black bull (dominant trait, B) and a homozygous recessive cow (bb), what would be the expected genotypic ratio of the offspring if the bull is heterozygous (Bb)?

Accepted Answer

50% Bb, 50% bb

Question 3

Which equation correctly represents the probability of producing a heterozygous offspring (Yy) from a cross between two heterozygous pea plants (Yy x Yy)?

Accepted Answer

$P(Yy) = \frac{1}{2}$

Question 4

Which of the following scenarios best illustrates the law of independent assortment?

Accepted Answer

A plant with genotype RrYy produces gametes with combinations of R and Y alleles independently.

Question 5

In a pedigree, if two parents without a trait have a child with the trait, what does this suggest about the inheritance pattern?

Accepted Answer

The trait is recessive.

Question 6

Which of the following is an example of incomplete dominance?

Accepted Answer

Red flowers crossed with white flowers produce pink flowers.

Question 7

If a woman with genotype I^A I^B and a man with genotype I^B i have a child, what is the probability that the child will have blood type AB?

Accepted Answer

$P(AB) = \frac{1}{2}$

Question 8

Which of the following best describes pleiotropy?

Accepted Answer

One gene influences several different traits.

Question 9

Which of the following is an example of polygenic inheritance?

Accepted Answer

Eye color, which is influenced by several genes.

Question 10

Epigenetic inheritance differs from Mendelian inheritance because:

Accepted Answer

It involves external modifications to DNA that turn genes on or off.

Question 11

A pea plant with genotype Yy produces gametes. According to Mendel's law of segregation, what proportion of its gametes will carry the y allele?

Accepted Answer

$\frac{1}{2}$

Question 12

Which of the following best explains codominance?

Accepted Answer

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

Question 13

If two heterozygous yellow pea plants (Yy) are crossed, what is the expected phenotypic ratio of their offspring?

Accepted Answer

3 yellow : 1 green

Question 14

Which of the following is NOT a deviation from Mendel's laws?

Accepted Answer

Complete dominance

Question 15

A pedigree shows that a trait skips generations and appears only when both parents are carriers. What is the most likely mode of inheritance?

Accepted Answer

Autosomal recessive

Question 16

Which of the following best describes the effect of environmental factors on epigenetic inheritance?

Accepted Answer

Environmental factors can modify gene expression without changing the DNA sequence.

Question 17

If a pea plant with genotype Yy is self-fertilized, what is the probability that an offspring will be homozygous recessive (yy)?

Accepted Answer

$\frac{1}{4}$

Question 18

Which of the following is an example of pleiotropy?

Accepted Answer

Sickle cell disease affecting multiple organ systems.

Question 19

Which of the following best describes polygenic inheritance?

Accepted Answer

Additive effects of two or more genes on a single phenotypic character.

Question 20

A black Angus bull (BB) is crossed with a black Angus cow (Bb). What percentage of their offspring will be homozygous dominant (BB)?

Accepted Answer

50%

Mendelian Genetics: Laws, Patterns, and Variations

Study Guide - Practice Questions

Study Guide - Flashcards