Question 1

Which of the following best explains why human offspring resemble their parents but are not identical to them?

Accepted Answer

Offspring inherit a combination of genes from both parents, and genetic recombination during meiosis creates unique combinations.

Question 2

Which process is responsible for reducing the chromosome number from diploid to haploid in sexually reproducing organisms?

Accepted Answer

Meiosis

Question 3

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

Accepted Answer

Prophase I; it increases genetic variation by exchanging DNA between homologous chromosomes.

Question 4

Which of the following events does NOT contribute to genetic variation in sexually reproducing populations?

Accepted Answer

Replication of DNA during S phase

Question 5

A plant species has a diploid number of 12 chromosomes. After meiosis, how many chromosomes will each gamete contain?

Accepted Answer

$$6$$

Question 6

Which of the following best describes the difference between mitosis and meiosis?

Accepted Answer

Mitosis produces two genetically identical cells, while meiosis produces four genetically unique cells.

Question 7

Which of the following is a direct result of crossing over during meiosis?

Accepted Answer

Exchange of genetic material between nonsister chromatids

Question 8

Why can’t crossing over occur during prophase II of meiosis?

Accepted Answer

Homologous chromosomes are no longer paired during prophase II.

Question 9

Which equation correctly represents the relationship between the number of possible chromosome combinations due to independent assortment and the haploid number $$n$$?

Accepted Answer

$$2^n$$

Question 10

A mutation occurs in a gene located on a chromosome. Which process is most likely to spread this mutation throughout a population over generations?

Accepted Answer

Natural selection acting on genetic variation

Question 11

Which of the following best explains why siblings from the same parents can look different from each other?

Accepted Answer

Genetic variation arises from independent assortment, crossing over, and random fertilization.

Question 12

In animals, what is the result of fertilization?

Accepted Answer

A diploid zygote

Question 13

Which of the following is NOT a difference between the life cycles of animals and plants?

Accepted Answer

Animals produce gametes by mitosis, while plants produce gametes by meiosis.

Question 14

Which of the following statements about meiosis is correct?

Accepted Answer

Meiosis produces four genetically unique haploid cells.

Question 15

If a human cell with 46 chromosomes undergoes meiosis, how many chromosomes will each resulting gamete have?

Accepted Answer

$$23$$

Question 16

Which of the following is the original source of genetic variation in a population?

Accepted Answer

Mutations

Question 17

Which event occurs during anaphase I of meiosis?

Accepted Answer

Homologous chromosomes separate, but sister chromatids remain joined at the centromere.

Question 18

Which of the following best describes the role of chiasmata during meiosis?

Accepted Answer

They are the sites where crossing over occurs between nonsister chromatids.

Question 19

Which of the following scenarios best illustrates the concept of random fertilization?

Accepted Answer

A single sperm fertilizes an egg, but which sperm and which egg are involved is completely by chance.

Question 20

Which of the following is NOT a mechanism that increases genetic diversity in sexually reproducing organisms?

Accepted Answer

Replication of DNA during interphase

Chapter 13: Meiosis and Sexual Life Cycles – Study Notes

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드