Question 1

Which of the following best describes the difference between asexual and sexual reproduction?

Accepted Answer

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

Question 2

What is the term for the specific location of a gene on a chromosome?

Accepted Answer

Locus

Question 3

In humans, how many chromosomes are found in a typical somatic cell, and what is the ploidy of these cells?

Accepted Answer

46 chromosomes, diploid

Question 4

Which process is responsible for reducing the chromosome number from diploid to haploid in gametes?

Accepted Answer

Meiosis

Question 5

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

Accepted Answer

Prophase I; it increases genetic variation

Question 6

If a human cell undergoes meiosis, how many genetically distinct gametes can be produced due to independent assortment alone? Use $$n = 23$$ for humans.

Accepted Answer

$$2^{23}$$

Question 7

Which of the following events is unique to meiosis and does NOT occur in mitosis?

Accepted Answer

Alignment of homologous pairs at the metaphase plate

Question 8

A zygote is formed by the union of two gametes. What is the chromosome number and ploidy of a human zygote?

Accepted Answer

46 chromosomes, diploid

Question 9

Which mechanism does NOT contribute to genetic variation in sexually reproducing organisms?

Accepted Answer

Replication of DNA during S phase

Question 10

A geneticist observes a cell with 46 chromosomes undergoing meiosis. After meiosis is complete, how many chromosomes will each daughter cell contain?

Accepted Answer

23

Question 11

Which of the following best explains why siblings from the same parents are genetically different from each other?

Accepted Answer

Crossing over and independent assortment during meiosis create new combinations of alleles

Question 12

Which of the following equations correctly represents the number of possible chromosome combinations due to independent assortment in a species with a haploid number $$n$$?

Accepted Answer

$$2^n$$

Question 13

During which stage of meiosis are homologous chromosomes separated?

Accepted Answer

Anaphase I

Question 14

Which structure forms during prophase I to hold homologous chromosomes together tightly and facilitate crossing over?

Accepted Answer

Synaptonemal complex

Question 15

A mutation occurs in a gene during DNA replication in a gamete. What is the evolutionary significance of this mutation?

Accepted Answer

It introduces a new allele that may contribute to genetic variation in the population.

Question 16

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

Accepted Answer

Four genetically distinct haploid cells are produced.

Question 17

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

Accepted Answer

They hold sister chromatids together until anaphase.

Question 18

If a sperm cell contains an X chromosome, what will be the sex chromosome composition of the resulting zygote if it fertilizes a normal egg?

Accepted Answer

XX

Question 19

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

Accepted Answer

Formation of recombinant chromosomes

Question 20

Why is sexual reproduction considered advantageous in changing environments?

Accepted Answer

It increases genetic variation, allowing populations to adapt to new conditions.

Meiosis and Sexual Life Cycles: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards