Question 1

Which of the following best describes the function of the centromere in a eukaryotic chromosome?

Accepted Answer

It is the region where spindle fibers attach to segregate chromosomes during cell division.

Question 2

A cell with a chromosome number of $2N$ undergoes mitosis. What will be the chromosome number in each daughter cell after division?

Accepted Answer

$2N$

Question 3

Which event during meiosis is primarily responsible for generating new combinations of alleles on the same chromosome?

Accepted Answer

Crossing over (recombination)

Question 4

What is the main evolutionary advantage of sexual reproduction in animals and plants?

Accepted Answer

It increases genetic diversity, which can be acted on by natural selection.

Question 5

During which stage of meiosis do homologous chromosomes pair and exchange genetic material?

Accepted Answer

Prophase I

Question 6

If a diploid organism has 8 chromosomes in its somatic cells, how many chromosomes will be present in each gamete after meiosis?

Accepted Answer

4

Question 7

Which of the following statements about homologous chromosomes is TRUE?

Accepted Answer

They carry the same genes but may have different alleles.

Question 8

What is the outcome of independent assortment during meiosis?

Accepted Answer

Homologous chromosomes are randomly distributed to daughter cells, increasing genetic variation.

Question 9

Which protein complex is essential for holding sister chromatids together until anaphase?

Accepted Answer

Cohesin

Question 10

A mutation disrupts the formation of chiasmata during meiosis. What is the most likely consequence?

Accepted Answer

Crossing over will not occur, reducing genetic diversity in gametes.

Question 11

Which of the following best explains why meiosis results in four genetically unique haploid cells?

Accepted Answer

Crossing over and independent assortment occur during meiosis I.

Question 12

In a human karyotype, how many pairs of homologous chromosomes are present in a typical somatic cell?

Accepted Answer

23

Question 13

Which of the following events occurs during metaphase I of meiosis?

Accepted Answer

Homologous chromosomes align at the metaphase plate.

Question 14

A geneticist observes that a certain organism produces gametes with abnormal chromosome numbers. Which meiotic process is most likely defective?

Accepted Answer

Segregation of homologous chromosomes during anaphase I

Question 15

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

Accepted Answer

Mitosis involves one cell division, meiosis involves two.

Question 16

If a mutation prevents the formation of the synaptonemal complex, what process will be directly affected?

Accepted Answer

Pairing and crossing over of homologous chromosomes

Question 17

Which of the following best describes a bivalent during meiosis?

Accepted Answer

A pair of homologous chromosomes, each consisting of two sister chromatids

Question 18

What is the ploidy level of a cell immediately after meiosis I but before meiosis II?

Accepted Answer

Haploid ($N$)

Question 19

Which of the following is NOT a hallmark event of meiosis I?

Accepted Answer

Segregation of sister chromatids

Question 20

A patient is diagnosed with a genetic disorder caused by nondisjunction during meiosis. Which stage is most likely to be implicated?

Accepted Answer

Anaphase I

Chromosomal Basis of Heredity: Cell Division, Mitosis, and Meiosis

Study Guide - Practice Questions