Question 1

Which of the following best describes the main purpose of meiosis in sexually reproducing organisms?

Accepted Answer

To reduce the chromosome number by half and generate genetic diversity in gametes

Question 2

During which substage of Prophase I does the synaptonemal complex first begin to form?

Accepted Answer

Zygotene

Question 3

If an organism has a diploid number of $$2n = 8$$, how many chromosomes and chromatids are present in a single cell during Metaphase II of meiosis?

Accepted Answer

$$n = 4$$ chromosomes and $$8$$ chromatids

Question 4

Which event is responsible for the physical connection between homologous chromosomes during Prophase I?

Accepted Answer

Assembly of the synaptonemal complex

Question 5

What is the significance of chiasmata during meiosis?

Accepted Answer

They are the sites where crossing over occurs, ensuring genetic recombination

Question 6

Which of the following best explains why gametes produced by meiosis are genetically unique?

Accepted Answer

Random alignment of homologous chromosomes during Metaphase I and crossing over during Prophase I

Question 7

At which stage of meiosis do homologous chromosomes separate, and what is the resulting ploidy of the daughter cells?

Accepted Answer

Anaphase I; haploid

Question 8

A cell with $$2n = 12$$ undergoes meiosis. How many chromosomes and chromatids are present in each daughter cell immediately after Telophase I?

Accepted Answer

$$n = 6$$ chromosomes and $$12$$ chromatids

Question 9

Which of the following is a key difference between mitosis and meiosis?

Accepted Answer

Homologous chromosomes pair and undergo crossing over in meiosis but not in mitosis

Question 10

In which substage of Prophase I does crossing over occur, and what is its genetic consequence?

Accepted Answer

Pachytene; increases genetic variation

Question 11

A mutation prevents the formation of the synaptonemal complex during meiosis. Which process would be most directly affected?

Accepted Answer

Synapsis and crossing over between homologous chromosomes

Question 12

If a human cell (2n = 46) is in Metaphase I of meiosis, how many chromosomes and chromatids are present in the cell?

Accepted Answer

$$46$$ chromosomes and $$92$$ chromatids

Question 13

Which of the following best describes the outcome of Meiosis II?

Accepted Answer

Separation of sister chromatids, resulting in haploid cells

Question 14

Which stage of meiosis is most directly responsible for Mendel’s law of independent assortment?

Accepted Answer

Metaphase I

Question 15

A cell in Anaphase II of meiosis contains $$n = 5$$ chromosomes. How many DNA molecules are present in the cell at this stage?

Accepted Answer

$$10$$

Question 16

Which of the following events occurs during Diplotene of Prophase I?

Accepted Answer

Chiasmata become visible as homologs start to separate

Question 17

Which process ensures that each gamete receives only one chromosome from each homologous pair?

Accepted Answer

Separation of homologous chromosomes during Anaphase I

Question 18

In a species with $$2n = 10$$, how many genetically unique gametes can be produced due to independent assortment alone?

Accepted Answer

$$2^5 = 32$

Question 19

Which of the following is true regarding the products of meiosis in animals?

Accepted Answer

The products are haploid and genetically variable

Question 20

Which of the following best explains why crossing over is important for evolution?

Accepted Answer

It generates new combinations of alleles, increasing genetic diversity

Cell Division II: Meiosis – Structure, Stages, and Comparison with Mitosis

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