BIOL 210 Module 4: Genetics - Meiosis and Chromosomal Inheritance Updated and Latest Questions and Correct Answers with Rationale

BIOL 210 Module 4: Genetics - Meiosis and
Chromosomal Inheritance Updated and Latest
Questions and Correct Answers with Rationale
1. During which phase of meiosis does crossing over occur?
A. Prophase I

B. Metaphase I

C. Prophase II

D. Anaphase I

Correct Answer: A
Explanation: Crossing over is the exchange of genetic material between non-sister
chromatids of homologous chromosomes, which occurs exclusively during Prophase I.

2. How many daughter cells are produced at the completion of meiosis II?
A. Two diploid cells

B. Four diploid cells

C. Two haploid cells

D. Four haploid cells
Correct Answer: D
Explanation: Meiosis involves two successive divisions resulting in four daughter cells,
each containing half the number of chromosomes (haploid) as the original parent cell.

3. In which stage do homologous chromosomes separate from one another?
A. Anaphase II

B. Anaphase I

C. Metaphase I

D. Telophase I

Correct Answer: B
Explanation: Anaphase I is characterized by the separation of homologous chromosome
pairs toward opposite poles, while sister chromatids remain attached.

4. Which process contributes to genetic variation by shuffling maternal and paternal
chromosomes?
A. Binary fission

,B. Mitosis

C. DNA replication

D. Independent assortment

Correct Answer: D
Explanation: Independent assortment occurs during Metaphase I when homologous pairs
align randomly at the metaphase plate, leading to various combinations of chromosomes in
gametes.

5. A human cell containing 22 autosomes and a Y chromosome is:
A. A somatic cell of a male

B. A zygote

C. An egg cell

D. A sperm cell
Correct Answer: D
Explanation: Human gametes (sperm and egg) are haploid, containing 23 chromosomes. A
sperm can carry either an X or a Y chromosome along with 22 autosomes.

6. What is the term for the physical pairing of homologous chromosomes during prophase I?
A. Synapsis

B. Segregation

C. Cytokinesis

D. Disjunction
Correct Answer: A
Explanation: Synapsis is the state where homologous chromosomes closely pair up to
form a complex known as a tetrad, allowing for crossing over.

7. At which stage of meiosis do sister chromatids finally separate?
A. Anaphase I

B. Metaphase II

C. Telophase II

D. Anaphase II
Correct Answer: D

, Explanation: Sister chromatids stay together during Meiosis I and only separate during
Anaphase II, similar to the process in mitosis.

8. If a cell has a diploid number of 12, how many chromosomes will be in each cell after
Meiosis I?
A. 12

B. 24

C. 6

D. 3
Correct Answer: C
Explanation: Meiosis I is a reductional division that halves the chromosome count from
diploid (2n) to haploid (n). If 2n=12, then n=6.

9. The site on a chromosome where crossing over has occurred is called a:
A. Kinetochore

B. Chiasma

C. Centromere

D. Centrosome

Correct Answer: B
Explanation: A chiasma is the X-shaped region where crossing over has occurred between
homologous non-sister chromatids.

10. Which of the following is a key difference between Meiosis and Mitosis?
A. DNA replication occurs before Mitosis but not before Meiosis
B. Meiosis involves two rounds of nuclear division while Mitosis involves one

C. Mitosis produces haploid cells while Meiosis produces diploid cells

D. Chromosomes only condense in Mitosis

Correct Answer: B
Explanation: Meiosis requires two divisions (Meiosis I and II) to reduce the chromosome
number, whereas Mitosis involves only one division to maintain the chromosome number.

11. Nondisjunction is defined as:
A. The exchange of genes between chromosomes

B. The failure of chromosomes to separate properly

C. The replication of DNA twice