Question 1

Which of the following was NOT a factor contributing to Mendel's success in discovering the basic principles of genetics?

Accepted Answer

He selected organisms that reproduced only by cross-fertilization.

Question 2

In Mendel's experiments with pea plants, what is the expected phenotypic ratio in the F2 generation of a monohybrid cross between true-breeding tall and dwarf plants?

Accepted Answer

$$3:1$$

Question 3

Which of the following best describes the Law of Segregation?

Accepted Answer

Each individual has two alleles for each gene, and these alleles separate during gamete formation so that each gamete receives only one allele.

Question 4

A pea plant with genotype $$Dd is $$crossed with a homozygous recessive plant ($$dd). $$What is the expected ratio of tall to dwarf offspring if tall is dominant?

Accepted Answer

$$1:1$$

Question 5

Which of the following statements about alleles is correct?

Accepted Answer

Alleles are different forms of the same gene.

Question 6

In a dihybrid cross between two heterozygous plants ($$YyRr 	imes YyRr$$), what is the expected phenotypic ratio in the F2 generation?

Accepted Answer

$$9:3:3:1$$

Question 7

Which of the following best explains the Law of Independent Assortment?

Accepted Answer

The segregation of alleles for one gene does not influence the segregation of alleles for another gene.

Question 8

A test cross is performed between a plant with an unknown genotype showing the dominant phenotype and a homozygous recessive plant. If all offspring show the dominant phenotype, what is the genotype of the unknown parent?

Accepted Answer

Homozygous dominant

Question 9

If the probability of inheriting allele $$A is$$ $$\frac{1}{2}$$ and the probability of inheriting allele $$B is$$ $$\frac{1}{4}$$, what is the probability of inheriting both $$A$$ and $$B$$ according to the product law of probabilities?

Accepted Answer

$$\frac{1}{8}$$

Question 10

In a trihybrid cross ($$AaBbCc 	imes AaBbCc$$), how many different phenotypes are expected in the F2 generation, assuming complete dominance for all traits?

Accepted Answer

8

Question 11

Which of the following is a correct definition of phenotype?

Accepted Answer

The observable characteristics of an organism as determined by the genotype and the environment.

Question 12

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 13

Which of the following is true about homozygous individuals?

Accepted Answer

They have two identical alleles for a particular gene.

Question 14

In a dihybrid test cross ($$YyRr 	imes yyrr$$), what is the expected phenotypic ratio among the offspring?

Accepted Answer

$$1:1:1:1$$

Question 15

Which of the following best describes a heterozygous genotype?

Accepted Answer

The two alleles for a particular gene are different.

Question 16

If a plant with genotype $$Aa is $$self-fertilized, what is the expected genotypic ratio among the offspring?

Accepted Answer

$$1:2:1$$

Question 17

Which of the following is NOT a correct statement about Mendel's principles?

Accepted Answer

All traits are inherited together as a single unit.

Question 18

A pedigree shows a trait that skips generations and appears equally in both sexes. What is the most likely mode of inheritance?

Accepted Answer

Autosomal recessive

Question 19

In a forked-line analysis for a trihybrid cross, what is the probability of obtaining an offspring with the genotype $$AabbCc$$ from parents that are both $$AaBbCc$$?

Accepted Answer

$$\frac{3}{64}$$

Question 20

Which of the following is a real-world application of pedigree analysis in human genetics?

Accepted Answer

Tracing the inheritance of genetic diseases in families.

Mendelian Genetics: Principles, Analysis, and Applications

Study Guide - Practice Questions

Study Guide - Flashcards