Question 1

Which of the following best describes the difference between autosomes and sex chromosomes in humans?

Accepted Answer

Autosomes are chromosomes not involved in determining sex, while sex chromosomes (X and Y) determine the sex of an individual.

Question 2

During meiosis, which process is primarily responsible for generating genetic diversity among gametes?

Accepted Answer

Random assortment of chromosomes and crossing over during meiosis I

Question 3

A human cell with a diploid number of chromosomes ($$2n = 46) $$undergoes meiosis. How many chromosomes will each resulting gamete contain?

Accepted Answer

$$23$$

Question 4

Which stage of meiosis is characterized by homologous chromosomes lining up along the metaphase plate?

Accepted Answer

Metaphase I

Question 5

If an organism is tetraploid, what does this mean regarding its chromosome number?

Accepted Answer

It has four complete sets of chromosomes.

Question 6

Which of the following is a direct consequence of independent assortment during meiosis?

Accepted Answer

Each gamete receives a random combination of maternal and paternal chromosomes.

Question 7

In the context of the paradox of sex, why might sexual reproduction be favored in a changing environment?

Accepted Answer

Sexual reproduction generates genetically diverse offspring, increasing the chances that some will survive environmental changes.

Question 8

Which of the following best explains the purifying selection hypothesis for the advantage of sexual reproduction?

Accepted Answer

Sexual reproduction enables populations to remove deleterious mutations more efficiently than asexual reproduction.

Question 9

During which phase of meiosis does crossing over occur, and what is its significance?

Accepted Answer

Prophase I; it increases genetic variation among gametes.

Question 10

A karyotype is most useful for which of the following purposes?

Accepted Answer

Identifying the number and appearance of chromosomes in a cell.

Question 11

Which of the following statements about gametes in humans is correct?

Accepted Answer

Gametes are haploid cells produced by meiosis.

Question 12

In animals and plants, what is the main biological difference between males and females?

Accepted Answer

Females produce larger gametes (eggs), while males produce smaller gametes (sperm).

Question 13

Which equation correctly represents the chromosome number in a human somatic cell and a human gamete?

Accepted Answer

Somatic cell: $$2n = 46$$, Gamete: $$n = 23$$

Question 14

Which of the following is NOT a source of genetic variation in sexually reproducing organisms?

Accepted Answer

Replication of DNA during S phase

Question 15

If a species has $$n = 12$$ chromosomes in its gametes, what is the diploid number of chromosomes in its somatic cells?

Accepted Answer

$$2n = 24$$

Question 16

Which of the following best describes the process and outcome of meiosis II?

Accepted Answer

Sister chromatids are separated, resulting in haploid cells.

Question 17

Why do females typically invest more resources in each gamete than males?

Accepted Answer

Female gametes (eggs) are larger and require more energy to produce than male gametes (sperm).

Question 18

Which of the following scenarios best illustrates the changing environment hypothesis for the advantage of sexual reproduction?

Accepted Answer

A population of animals faces new predators and rapidly changing climate, favoring genetically diverse offspring.

Question 19

Which of the following is true regarding the Good Genes Model of sexual selection?

Accepted Answer

It predicts that females choose mates based on traits that reflect the genetic quality of the male.

Meiosis and Sexual Reproduction: Study Notes

Study Guide - Practice Questions