Deck 9: Meiosis and the Genetic Basis of Sexual Reproduction

Question 1

Which of the following does not occur twice during meiosis?

A) production of daughter nuclei
B) spindle formation
C) pairing of homologous chromosomes
D) separation of genetic material
E) alignment of chromosomes at the spindle equator

Answer 1

C
Explanation: Pairing of homologous chromosomes, or synapsis, only occurs during prophase I.

Question 2

Which of the following is a correct match?

A) separation of tetrads - anaphase II
B) synapsis - metaphase I
C) separation of sister chromatids - anaphase I
D) synapsis - prophase II
E) separation of sister chromatids - anaphase II

Answer 2

E
Explanation: Sister chromatids separate during anaphase II, but not during anaphase I. The homologous chromosomes of a tetrad separate during anaphase I, but not during anaphase II. Synapsis only occurs during prophase I, so separation of sister chromatids - anaphase II is the only correct match.

Question 3

In each gamete following telophase II, how many copies of each gene is/are present?

A) 1
B) 2
C) 3
D) 4
E) 8

Answer 3

A
Explanation: After DNA duplication, each chromosome consists of two sister chromatids, each containing one copy of each gene. With two homologues of each chromosome in a diploid, there will be four copies of each gene at prophase I. After separation of homologues, there will be two copies present during prophase II. During telophase II, the sister chromatids are separated, leaving one homologue per cell.

Question 4

Which of the diagrams best illustrates the appearance of a chromosome or chromosome pair at the end of prophase I?

A) diagram 1
B) diagram 2
C) diagram 3
D) diagram 4
E) diagram 5

Question 5

During prophase I, a diploid organism contains how many copies of each gene?

A) 1
B) 2
C) 3
D) 4
E) 8

Question 6

Which of the following lists is in the correct order, from the least inclusive to the most inclusive?

A) allele - gene - chromosome
B) gene - allele - chromosome
C) allele - chromosome - gene
D) chromosome - gene - allele
E) gene - chromosome - allele

Question 7

During meiosis I, the homologous chromosomes of a tetrad

A) face the same spindle pole.
B) face both spindle poles.
C) face opposite spindle poles.
D) do not face spindle poles but are aligned at the spindle equator.
E) undergo separation of sister chromatids.

Question 8

During prophase II, a diploid organism contains how many copies of each gene?

A) 1
B) 2
C) 3
D) 4
E) 8

Question 9

Which of the diagrams represent a chromosome or chromosome pair in a cell at the end of prophase II?

A) diagram 1
B) diagram 2
C) diagram 3
D) diagram 4
E) diagram 5

Question 10

In the human life cycle,

A) meiosis produces haploid gametes, and fertilization creates a diploid cell that divides by mitosis to produce a new individual.
B) mitosis produces haploid gametes, and fertilization creates a diploid cell that divides by meiosis to produce a new individual.
C) diploid gametes reproduce by meiosis to produce haploid daughter cells that divide by mitosis to produce a new individual.
D) diploid gametes reproduce by mitosis to produce diploid daughter cells that divide by meiosis to produce a new individual.
E) a haploid zygote reproduces by meiosis to produce diploid daughter cells that divide by mitosis to produce a new individual.

Question 11

Which of the following statements is correct?

A) Meiosis involves two divisions and produces four nonidentical daughter nuclei.
B) Meiosis involves one division and produces two nonidentical daughter nuclei.
C) Mitosis involves one division and produces two nonidentical daughter nuclei.
D) Mitosis involves two divisions and produces four identical daughter nuclei.
E) Meiosis involves two divisions and produces four identical daughter nuclei.

Question 12

During crossing-over,

A) genetic material is exchanged between sister chromatids, resulting in new combinations of alleles.
B) genetic material is exchanged between nonsister chromatids, resulting in new combinations of alleles.
C) sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles.
D) nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles.
E) one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles.

Question 13

One major difference between meiosis I and meiosis II is that

A) crossing-over occurs in prophase of meiosis I but not in prophase of meiosis II.
B) sister chromatids are separated during meiosis I, while homologous chromosomes are separated during meiosis II.
C) the resulting cells at the end of meiosis I are diploid, while the cells at the end of meiosis II are haploid.
D) in telophase of meiosis I, four daughter cells form from the parent cell, and in telophase of meiosis II, each parent cell gives rise to two daughter cells.
E) in meiosis I there is no pairing of chromosomes while homologues pair in meiosis II.

Question 14

Which statement best describes how the members of a tetrad are separated during meiosis I?

A) The two homologous chromosomes of a tetrad separate into different daughter nuclei.
B) The sister chromatids of each chromosome separate into different daughter nuclei.
C) The nonsister chromatids of each tetrad separate into different daughter nuclei.
D) The two homologous chromosomes of a tetrad separate into one of two daughter nuclei.
E) The two homologous chromosomes of a tetrad are duplicated and separate into each daughter nucleus.

Question 15

Armadillos have a diploid chromosome number of 64. At prophase I, an armadillo's cell would have ________ tetrads present.

A) 16
B) 32
C) 64
D) 80
E) 128

Question 16

A dyad consists of

A) two homologous chromosomes consisting of two sister chromatids.
B) two homologous chromosomes consisting of two nonsister chromatids.
C) one duplicated chromosome consisting of two nonsister chromatids.
D) one duplicated chromosome consisting of two sister chromatids.
E) two homologous chromosomes consisting of a single DNA strand each.

Question 17

A tetrad is composed of

A) two chromosomes with two sister chromatids each.
B) two sister chromatids with separate centromeres.
C) four chromosomes with two sister chromatids each.
D) four sister chromatids, each with its own centromere.
E) four sister chromatids attached at a common centromere.

Question 18

The possibility of Down syndrome increases as the mother's age increases because

A) her DNA is damaged through an accumulation of replication errors.
B) her DNA stops checking for replication errors.
C) fertilization no longer occurs correctly with older eggs.
D) the contents of the egg contain the wrong signals for the correct development of the fetus.
E) the possibility of nondisjunction increases.

Question 19

Which of the following processes does not contribute to creating genetic variability in the offspring?

A) crossing-over
B) independent assortment of chromosomes
C) pairing of homologous chromosomes
D) interkinesis
E) having different alleles of the same gene

Question 20

During G₁ stage of interphase, a diploid organism contains how many copies of each gene?

A) 1
B) 2
C) 4
D) 8
E) 16

Question 21

Metaphase II is more similar to metaphase of mitosis than to metaphase I because

A) in metaphase I, tetrads align together at the spindle equator.
B) in metaphase II, tetrads align separately at the spindle equator.
C) in metaphase of mitosis, tetrads align separately at the spindle equator.
D) in metaphase II, dyads align separately at the spindle equator.
E) in metaphase I, dyads align separately at the spindle equator.

Question 22

The failure of sister chromatids to separate during meiosis is called

A) synapsis.
B) crossing-over.
C) tetrad formation.
D) disjunction.
E) nondisjunction.

Question 23

Which of the following phases results in separation of sister chromatids into daughter chromosomes?

A) anaphase of mitosis
B) anaphase I, anaphase II, and anaphase of mitosis
C) anaphase I and anaphase II
D) anaphase I and anaphase of mitosis
E) anaphase II and anaphase of mitosis

Question 24

Goats have a diploid chromosome number of 60. At prophase I, each cell would have ________ tetrads present, for a total of ________ chromatids.

A) 30; 120
B) 30; 60
C) 60; 120
D) 60; 240
E) 30; 240

Question 25

Which of the following processes and products are paired correctly?

A) spermatogenesis - 2n zygote
B) oogenesis - 2n zygote
C) oogenesis - 1n gamete
D) meiosis - 2n zygote
E) mitosis - 1n gamete

Question 26

Which of the following is not a function of meiosis?

A) cause an organism to grow
B) create genetic variability
C) reduce the chromosome number in gametes
D) keep the chromosome number constant from one generation to the next
E) produce gametes

Question 27

For the figure shown here, indicate the correct stage of meiosis and diploid chromosome number.

A) metaphase II, 2n=4
B) metaphase II, 2n=2
C) metaphase II, 2n=8
D) metaphase I, 2n=4
E) metaphase I, 2n=8

Question 28

Swyer syndrome 46, XY, female appearance), would most likely result from

A) nondisjunction during meiosis I in the female parent.
B) nondisjunction during meiosis I in the male parent.
C) nondisjunction during meiosis II in the female parent.
D) nondisjunction during meiosis II in the male parent.
E) normal disjunction during meiosis, but deletion of a portion of the Y chromosome in the male parent.

Question 29

A human egg with 22 chromosomes that is fertilized by a normal sperm will result in

A) a zygote with trisomy.
B) a zygote with disomy.
C) a zygote with monosomy.
D) a zygote with normal chromosome number.
E) nondisjunction during subsequent mitosis.

Question 30

Klinefelter syndrome can result from nondisjunction during

A) meiosis I in the female parent.
B) meiosis I in the male parent.
C) meiosis I in either female parent.
D) meiosis I or II in the male parent.
E) meiosis I or II in either parent.

Question 31

Turner syndrome is associated with which of the following karyotypes?

A) 47, XXY
B) 47, XXX
C) 46, XY
D) 47, XY, trisomy 21
E) 45, XO

Question 32

For the figure shown here, indicate the correct stage of meiosis and the diploid number of the cell.

A) prophase I, 2n=4
B) prophase II, 2n=4
C) metaphase I, 2n=4
D) metaphase II, 2n=2
E) anaphase II, 2n=2

Question 33

Interphase differs from interkinesis because

A) DNA is duplicated during interphase, but not during interkinesis.
B) DNA is duplicated during interkinesis, but not during interphase.
C) homologous chromosomes separate during interkinesis, but not during interphase.
D) homologous chromosomes separate during interphase, but not during interkinesis.
E) interkinesis only occurs during mitosis, while interphase occurs during both meiosis and mitosis.

Question 34

An individual with the karyotype 48, XYYY would have how many Barr bodies?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 35

Which of the following human syndromes is a monosomy?

A) Turner syndrome
B) Klinefelter syndrome
C) Down syndrome
D) Swyer syndrome
E) Barr body syndrome

Question 36

Following meiosis I, the daughter cells are ________; following meiosis II, the daughter cells are ________; and following mitosis, the daughter cells are ________.

A) diploid; haploid; diploid
B) diploid; diploid; haploid
C) haploid; haploid; diploid
D) haploid; haploid; haploid
E) diploid; diploid; diploid

Question 37

An individual with Swyer syndrome 46, XY) differs from an individual with Klinefelter syndrome 47, XXY) because

A) an individual with Swyer syndrome has a Barr body, while an individual with Klinefelter syndrome does not.
B) an individual with Klinefelter syndrome has a functional SRY gene on his Y chromosome, whereas an individual with Swyer syndrome does not.
C) both individuals have a functional SRY gene, but the extra X chromosome makes the individual with Klinefelter syndrome appear female.
D) neither individual has a functional SRY gene, but the X chromosome of the individual with Swyer syndrome has a functional SRY and appears male.
E) an individual with Swyer syndrome lacks a functional SRY gene, but appears male because it has moved to the X chromosome as in an individual with Klinefelter syndrome.

Question 38

During meiosis II,

A) homologous chromosomes line up separately, with sister chromatids facing the same spindle pole.
B) chromosomes line up separately, with sister chromatids facing opposite spindle poles.
C) chromosomes line up separately, with sister chromatids facing the same spindle pole.
D) homologous chromosomes line up separately, with sister chromatids facing opposite spindle poles.
E) homologous chromosomes line up together, with sister chromatids facing opposite spindle poles.

Question 39

The failure of sister chromatids to separate would result in how many normal gametes?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 40

For the figure shown here, indicate the correct stage of meiosis and diploid chromosome number.

A) anaphase I, 2n=16
B) anaphase II, 2n=16
C) anaphase I, 2n=8
D) anaphase II, 2n=8
E) anaphase II, 2n=4

Question 41

The human life cycle consists of

A) adults who are haploid and produce diploid gametes; these gametes fuse to produce a haploid zygote which grows into an adult.
B) zygotes who are haploid fuse to produce a diploid gamete which grows into an adult.
C) gametes that are diploid and produce haploid zygotes; these grow into haploid adults.
D) adults who are diploid and produce haploid gametes; these gametes fuse to produce a diploid zygote which grows into an adult.
E) adults that are diploid who produce zygotes that are also diploid.

Question 42

Which of the following is not correct about crossing-over?

A) Crossing-over is preceded by a process known as synapsis, where homologous chromosomes attach to each other.
B) Crossing-over results in greater genetic variability in offspring.
C) Crossing-over is only detectable when it occurs between sister chromatids.
D) Crossing-over occurs during prophase I when homologous chromosomes line up prior to separation.
E) In humans, crossing-over occurs an average of approximately two events per chromosome.

Question 43

It would be possible for a male and a female to have exactly the same ________, but they would have to differ in ________.

A) diploid chromosomes; haploid chromosomes
B) autosomes; sex chromosomes
C) homologues; autosomes
D) karyotype; sex chromosomes
E) karyotype; autosomes

Question 44

You are looking at a cell under a microscope and see what appears to be several "X" structures being pulled to each side of the cell. What stage of meiosis are you looking at?

A) anaphase I
B) prophase I
C) prophase II
D) metaphase I
E) anaphase II

Question 45

All but which one of the following results from nondisjunction?

A) trisomy
B) diploidy
C) monosomy
D) polyploidy
E) Down syndrome

Question 46

Camels have a diploid chromosome number of 70. At prophase II, each cell would contain how many chromatids?

A) 0
B) 35
C) 70
D) 140
E) 280

Question 47

Camels have a diploid chromosome number of 70. At prophase II, each cell would contain how many tetrads?

A) 0
B) 35
C) 70
D) 140
E) 280

Question 48

During which stage of meiosis will the pairs of homologous chromosomes line up?

A) metaphase I
B) metaphase II
C) metaphase
D) anaphase I
E) prophase II

Question 49

Chromosomes that occur in pairs and code for the same traits are called ________ chromosomes; these do not include the ________ chromosomes, which code for gender.

A) homologous; autosomes
B) autosomes; homologous
C) diploid; haploid
D) homologous: sex
E) sex; autosomes

Question 50

Crossing-over between sister chromatids does not result in recombination of genetic material, while crossing-over between nonsister chromatids does because

A) sister chromatids have the same alleles, while nonsister chromatids have different ones.
B) sister chromatids have the same genes, while nonsister chromatids have different ones.
C) sister chromatids have the same alleles but different genes, while nonsister chromatids have different alleles but the same genes.
D) nonsister chromatids have the same alleles, while sister chromatids have different ones.
E) nonsister chromatids have the same genes, while sister chromatids have different ones.

Question 51

Which of the following is not a symptom of Down syndrome?

A) short stature
B) eyelid fold
C) stubby fingers
D) tall stature
E) fissured tongue

Question 52

It is essential that germ cells undergo meiosis so that

A) the cells can differentiate.
B) the fertilized egg has half the genetic material of the parents.
C) the number of chromosomes is cut in half in gametes.
D) genetic disorders are prevented.
E) genetic diversity is reduced.

Question 53

Which of the following statements is true?

A) Chromosomes are classified into two categories: the sex chromosomes that determine gender and autosomes that determine non-gender related traits.
B) Homologous chromosomes differ in banding patterns, the traits they code for, and size.
C) While sex chromosomes determine different genders, they look the same until they are stained.
D) In humans all 46 chromosomes have an identical match called the homologue.
E) Chromosomes are classified into two categories: autosomes that determine gender and the sex chromosomes that determine non-gender related traits.