Question 1

Which of the following best explains why offspring produced by sexual reproduction are genetically unique compared to their parents?

Accepted Answer

Because sexual reproduction involves independent assortment, crossing over, and random fertilization.

Question 2

A human somatic cell contains 46 chromosomes. After meiosis, how many chromosomes will each gamete contain?

Accepted Answer

$$23$$

Question 3

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

Accepted Answer

Crossing over during Prophase I

Question 4

If a diploid cell with $$2n = 8$$ undergoes meiosis, how many chromosomes will each resulting gamete have?

Accepted Answer

$$4$$

Question 5

Which of the following statements about mitosis and meiosis is correct?

Accepted Answer

Mitosis conserves chromosome number, while meiosis reduces it by half.

Question 6

During which stage of meiosis do homologous chromosomes separate?

Accepted Answer

Anaphase I

Question 7

A cell at the start of meiosis contains $$28$$ chromatids. After meiosis is complete, how many chromosomes will each daughter cell contain?

Accepted Answer

$$7$$

Question 8

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

Accepted Answer

Replication of DNA during S phase

Question 9

In humans, what is the ploidy of the zygote immediately after fertilization?

Accepted Answer

Diploid ($$2n)$$

Question 10

Which of the following best describes a karyotype?

Accepted Answer

An ordered display of the pairs of metaphase chromosomes in a cell

Question 11

A plant species has a diploid number of $$2n = 12. $$How many possible combinations of chromosomes can be produced in its gametes by independent assortment alone?

Accepted Answer

$$2^{6} = 64$

Question 12

Which of the following is a key difference between asexual and sexual reproduction?

Accepted Answer

Asexual reproduction produces genetically identical offspring, while sexual reproduction produces genetically diverse offspring.

Question 13

Which process restores the diploid number of chromosomes in sexually reproducing organisms?

Accepted Answer

Fertilization

Question 14

Which of the following is true about homologous chromosomes?

Accepted Answer

They carry the same genes at the same loci, but may have different alleles.

Question 15

During which phase of meiosis does crossing over occur?

Accepted Answer

Prophase I

Question 16

Which of the following best explains why asexual reproduction can be advantageous in stable environments?

Accepted Answer

It allows for rapid population growth without the need for a mate.

Question 17

If a cell has half the number of chromosomes and one-fourth the amount of DNA compared to a cell that has just completed DNA replication, what stage is it most likely in?

Accepted Answer

After meiosis II

Question 18

Which of the following is NOT a feature unique to meiosis (and not found in mitosis)?

Accepted Answer

Production of genetically identical cells

Question 19

Why is random fertilization a significant source of genetic variation?

Accepted Answer

Because each gamete contains a unique combination of chromosomes, and any sperm can fuse with any egg.

Question 20

Which of the following best describes the alternation of generations in plants?

Accepted Answer

Plants alternate between a multicellular diploid stage and a multicellular haploid stage.

Sexual Reproduction and Genetic Variation: Meiosis and Life Cycles

Study Guide - Practice Questions

Study Guide - Flashcards