Question 1

Which of the following best describes the difference between a somatic cell and a gamete in humans?

Accepted Answer

A somatic cell contains two sets of chromosomes, while a gamete contains one set.

Question 2

What is the diploid number $$(2n)$$ and haploid number $$(n) of an $$African clawed frog whose somatic cells have 36 chromosomes?

Accepted Answer

$$2n = 36$$, $$n = 18$$

Question 3

Which event occurs during meiosis I but not during mitosis?

Accepted Answer

Formation of tetrads and crossing over

Question 4

Why is crossing over during meiosis important for genetic variation?

Accepted Answer

It allows homologous chromosomes to exchange genetic material, creating recombinant chromosomes.

Question 5

A human male has which combination of sex chromosomes?

Accepted Answer

XY

Question 6

Which of the following mechanisms does NOT contribute to genetic variation in sexually reproducing organisms?

Accepted Answer

Replication of DNA during mitosis

Question 7

If a human cell undergoes meiosis, how many chromosomes will each resulting gamete contain?

Accepted Answer

23

Question 8

Which statement about homologous chromosomes is correct?

Accepted Answer

They carry genes controlling the same inherited characters at the same loci.

Question 9

What is the primary evolutionary advantage of sexual reproduction over asexual reproduction?

Accepted Answer

It increases genetic variation, which can enhance adaptability to changing environments.

Question 10

During which phase of meiosis do homologous chromosomes separate?

Accepted Answer

Anaphase I

Question 11

How many possible combinations of chromosomes can be produced in human gametes due to independent assortment alone?

Accepted Answer

$$2^{23}$$

Question 12

Which term describes the physical location of a gene on a chromosome?

Accepted Answer

Locus

Question 13

What is the result of fertilization in humans?

Accepted Answer

A diploid zygote

Question 14

Which process is responsible for producing gametes in animals?

Accepted Answer

Meiosis

Question 15

Which of the following is NOT a difference between mitosis and meiosis?

Accepted Answer

Mitosis produces gametes, meiosis produces somatic cells.

Question 16

Which statement about the genetic code is correct?

Accepted Answer

Each codon encodes for a specific amino acid in a protein chain.

Question 17

Which of the following best explains why all life has a common origin?

Accepted Answer

Genes with similar functions in different organisms are similar in structure and DNA sequence.

Question 18

Which phase of meiosis is called the reductional division?

Accepted Answer

Meiosis I

Question 19

What is the significance of random fertilization in genetic variation?

Accepted Answer

It allows any sperm to fuse with any ovum, creating a zygote with a unique combination of chromosomes.

Question 20

Which of the following is a direct result of mutations in DNA?

Accepted Answer

Creation of different alleles

Meiosis, Sexual Life Cycles, and Genetic Variation: Principles of Genetics (BIO 2001, Chapter 13)

Study Guide - Practice Questions