CHAPTER 13 PRACTICE QUESTIONS

The figure represents the nucleus of an animal cell about to enter mitosis. How many different
chromosomes are present in the diagram?
A) 1
B) 4
C) 8
D) 16

B) 4

2) Which of the following statements is true of a species that has a chromosome number of 2n =
16?
A) The species is diploid and has 32 chromosomes per cell.
B) The species has 16 sets of chromosomes per cell.
C) Each diploid cell has eight homologous pairs of chromosomes.
D) A gamete from this species has four chromosomes

C) Each diploid cell has eight homologous pairs of chromosomes.

3) A triploid cell contains three sets of homologous chromosomes. Which of the following
describes the chromosomes in a triploid cell where n = 6?
A) The cell has 3 homologous pairs of chromosomes at the beginning of mitosis.
B) The cell has 12 total chromosomes at the end of mitosis.
C) The cell has 18 total chromosomes in 6 sets.

D) The cell has 24 sister chromatids when in prophase I.

C) The cell has 18 total chromosomes in 6 sets.

4) Which of the following statements best describes homologous chromosomes?
A) They were inherited from the same parent.
B) They carry information for the same traits.
C) They carry the same alleles.
D) They align on the metaphase plate in meiosis II.

B) They carry information for the same traits.

5) Many diploid organisms produce haploid gametes for reproduction. Which of the following
best describes how the diploid number of chromosomes is restored in the offspring of these
organisms?
A) DNA replication creates homologous chromosomes
B) independent assortment in meiosis allows random combinations of chromosomes
C) synapsis during prophase of meiosis I creates random combinations of alleles
D) fertilization combines chromosomes from each parent into resulting zygote

D) fertilization combines chromosomes from each parent into resulting zygote

6) A cell has completed meiosis I and the first cytokinesis, and is just beginning meiosis II.
Which of the following statements describes its genetic contents?
A) It has half the amount of DNA as the cell that began meiosis.
B) It has twice the DNA of the cell that began meiosis.
C) It has one-fourth the DNA and one-half the chromosomes as the cell that began meiosis.
D) It is genetically identical to the other cells produced by this cytokinesis.

A) It has half the amount of DNA as the cell that began meiosis.

7) Which of the following statements describes the chromosomal makeup of each daughter cell
after telophase of meiosis I?
A) The cells are diploid, and the chromosomes are each composed of a single chromatid.
B) The cells are diploid, and the chromosomes are each composed of two chromatids.
C) The cells are haploid, and the chromosomes are each composed of a single chromatid.
D) The cells are haploid, and the chromosomes are each composed of two chromatids.

D) The cells are haploid, and the chromosomes are each composed of two chromatids.

8) Which of the following processes occurs in meiosis but not in mitosis?
A) chromosome replication
B) synapsis of chromosomes
C) alignment of chromosomes at the metaphase plate
D) condensation of chromosomes

B) synapsis of chromosomes

9) Which of the following processes has just occurred when chiasmata can first be viewed under
a microscope?
A) meiosis II
B) anaphase II
C) prophase I
D) the separation of homologs

C) prophase I

10) For the following question, match the key event of meiosis with the stages listed below.
I. Prophase I V. Prophase II
II. Metaphase I VI. Metaphase II
III. Anaphase I VII. Anaphase II
IV. Telophase I VIII. Telophase II

Homologous chromosomes are aligned at the middle of the spindle.
A) I
B) II
C) IV
D) VI

B) II

11) Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The
drawings in the figure below represent the chromosomes. Refer to the drawings and answer the
following question(s).
Which diagram represents anaphase I of meiosis?
A) I
B) II
C) IV
D) V

A) I

12) Cells from a diploid protist with n=1 are followed through mitosis and meiosis. The
drawings in the figure below represent the chromosomes. Refer to the drawings and answer the
following question(s).

Which diagram represents prophase of mitosis?
A) I
B) III
C) IV
D) VI

B) III

13) Somatic cells of roundworms have four individual chromosomes per cell. How many
chromosomes would you expect to find in an ovum from a roundworm?
A) four
B) two
C) eight
D) a diploid number

B) two

14) Which of the following statements describes a major difference between meiosis II and
mitosis in a diploid animal?
A) Homologous chromosomes align on the metaphase plate in meiosis II but not in mitosis.
B) Sister chromatids separate in mitosis, and homologous chromosomes separate in meiosis II.
C) Meiosis II occurs in a haploid cell, while mitosis occurs in diploid cells.
D) Crossing over of chromosomes takes place in meiosis II but not in mitosis

C) Meiosis II occurs in a haploid cell, while mitosis occurs in diploid cells.

15) Crossing over of chromosomes normally takes place during which of the following
processes?
A) meiosis II
B) meiosis I
C) mitosis
D) mitosis and meiosis II

B) meiosis I

16) During which of the following processes do homologous pairs of chromosomes align
adjacent to one another at the metaphase plate of a cell?
A) metaphase of mitosis

B) metaphase I of meiosis
C) telophase II of meiosis
D) metaphase II of meiosis

B) metaphase I of meiosis

17) During which of the following phases of meiosis do centromeres split and sister chromatids
migrate to opposite poles of the cell?
A) anaphase I
B) telophase I
C) anaphase II
D) telophase II

C) anaphase II

18) A (hypothetical) diploid organism has different genes that control wing length and wing
color.
A female of this species with short blue-colored wings has a chromosome pair with two short-
wing alleles and a second chromosome pair with one blue-wing allele and one orange-wing
allele. The eggs from this individual will have which of the following combinations of alleles?
A) all of the eggs will have alleles for short blue-colored wings
B) all of the eggs will have alleles for short orange-colored wings
C) 1/2 of the eggs will have alleles for short blue-colored wings and ½ will have alleles for short
orange-colored wings
D) 3/4 of the eggs have alleles for short blue-colored wings and ¼ of the eggs have alleles for
short orange-colored wings.

C) 1/2 of the eggs will have alleles for short blue-colored wings and ½ will have alleles for short
orange-colored wings

19) For a species with a haploid number of 23 chromosomes, how many different combinations
of maternal and paternal chromosomes are possible for the gametes based on the independent
assortment of chromosomes during meiosis?
A) 23
B) 46
C) about 1,000
D) about 8 million

D) about 8 million

20) Which of the following results when homologous chromosomes cross over in meiosis?
A) Two sister chromatids get tangled, resulting in one re-sequencing its DNA.
B) Two sister chromatids exchange identical pieces of DNA.
C) Corresponding segments of non-sister chromatids are exchanged.
D) DNA repair machinery alters maternal alleles so they match paternal ones

C) Corresponding segments of non-sister chromatids are exchanged.