Question 1

Which of these statements is false?

Accepted Answer

A)  In humans, each of the 22 maternal autosomes has a homologous paternal chromosome. 
B)  In humans, the 23rd pair, the sex chromosomes, determines whether the person is female (XX) or male (XY). 
C)  Single, haploid (n) sets of chromosomes in ovum and sperm unite during fertilization, forming a diploid (2n), single-celled zygote. 
D)  At sexual maturity, ovaries and testes produce diploid gametes by meiosis. 
E)  Sexual life cycles differ with respect to the relative timing of meiosis and fertilization. 
A)  In humans, each of the 22 maternal autosomes has a homologous paternal chromosome. 
B)  In humans, the 23rd pair, the sex chromosomes, determines whether the person is female (XX) or male (XY). 
C)  Single, haploid (n) sets of chromosomes in ovum and sperm unite during fertilization, forming a diploid (2n), single-celled zygote. 
D)  At sexual maturity, ovaries and testes produce diploid gametes by meiosis. 
E)  Sexual life cycles differ with respect to the relative timing of meiosis and fertilization.

Question 2

The karyotype of one species of primate has 48 chromosomes. In a particular female, cell division goes awry and she produces one of her eggs with an extra chromosome (25). The most probable source of this error would be a mistake in which of the following?

Accepted Answer

A)  mitosis in her ovary 
B)  metaphase I of one meiotic event 
C)  telophase II of one meiotic event 
D)  telophase I of one meiotic event 
E)  either anaphase I or II 
A)  mitosis in her ovary 
B)  metaphase I of one meiotic event 
C)  telophase II of one meiotic event 
D)  telophase I of one meiotic event 
E)  either anaphase I or II

Question 3

The following question refers to the essential steps in meiosis described below.
1. Formation of four new nuclei, each with half the chromosomes present in the parental nucleus
2. Alignment of tetrads at the metaphase plate
3. Separation of sister chromatids
4. Separation of the homologs; no uncoupling of the centromere
5. Synapsis; chromosomes moving to the middle of the cell in pairs
-For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes?

Accepted Answer

A)  23 
B)  46 
C)  460 
D)  920 
E)  about 8 million 
A)  23 
B)  46 
C)  460 
D)  920 
E)  about 8 million

Question 4

How is natural selection related to sexual reproduction as opposed to asexual reproduction?

Accepted Answer

A)  Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction. 
B)  Sexual reproduction results in the most appropriate and healthiest balance of two sexes in the population. 
C)  Sexual reproduction results in the greatest number of new mutations. 
D)  Sexual reproduction allows the greatest number of offspring to be produced. 
E)  Sexual reproduction utilizes far less energy than asexual reproduction. 
A)  Sexual reproduction results in many new gene combinations, some of which will lead to differential reproduction. 
B)  Sexual reproduction results in the most appropriate and healthiest balance of two sexes in the population. 
C)  Sexual reproduction results in the greatest number of new mutations. 
D)  Sexual reproduction allows the greatest number of offspring to be produced. 
E)  Sexual reproduction utilizes far less energy than asexual reproduction.

Question 5

Refer to the life cycles illustrated in Figure 13.1 to answer the following questions.
   
Figure 13.1
-Which of the life cycles is typical for animals?

Accepted Answer

A)  I only 
B)  II only 
C)  III only 
D)  I and II 
E)  I and III 
A)  I only 
B)  II only 
C)  III only 
D)  I and II 
E)  I and III

Question 6

A triploid cell contains three sets of chromosomes. If a cell of a usually diploid species with 42 chromosomes per cell is triploid, this cell would be expected to have which of the following?

Accepted Answer

A)  63 chromosomes in 31 1/2 pairs 
B)  63 chromosomes in 21 sets of 3 
C)  63 chromosomes, each with three chromatids 
D)  21 chromosome pairs and 21 unique chromosomes 
A)  63 chromosomes in 31 1/2 pairs 
B)  63 chromosomes in 21 sets of 3 
C)  63 chromosomes, each with three chromatids 
D)  21 chromosome pairs and 21 unique chromosomes

Question 7

If an organism is diploid and a certain gene found in the organism has 18 known alleles (variants), then any given organism of that species can/must have which of the following?

Accepted Answer

A)  at most, 2 alleles for that gene 
B)  up to 18 chromosomes with that gene 
C)  up to 18 genes for that trait 
D)  a haploid number of 9 chromosomes 
E)  up to, but not more than, 18 different traits 
A)  at most, 2 alleles for that gene 
B)  up to 18 chromosomes with that gene 
C)  up to 18 genes for that trait 
D)  a haploid number of 9 chromosomes 
E)  up to, but not more than, 18 different traits

Question 8

Refer to the life cycles illustrated in Figure 13.1 to answer the following questions.
   
Figure 13.1
-In a life cycle such as that shown in part III of Figure 13.1, if the zygote's chromosome number is 10, which of the following will be true?

Accepted Answer

A)  The sporophyte's chromosome number per cell is 10 and the gametophyte's is 5. 
B)  The sporophyte's chromosome number per cell is 5 and the gametophyte's is 10. 
C)  The sporophyte and gametophyte each have 10 chromosomes per cell. 
D)  The sporophyte and gametophyte each have 5 chromosomes per cell. 
E)  The sporophyte and gametophyte each have 20 chromosomes per cell. 
A)  The sporophyte's chromosome number per cell is 10 and the gametophyte's is 5. 
B)  The sporophyte's chromosome number per cell is 5 and the gametophyte's is 10. 
C)  The sporophyte and gametophyte each have 10 chromosomes per cell. 
D)  The sporophyte and gametophyte each have 5 chromosomes per cell. 
E)  The sporophyte and gametophyte each have 20 chromosomes per cell.

Question 9

The following question refers to the essential steps in meiosis described below.
1. Formation of four new nuclei, each with half the chromosomes present in the parental nucleus
2. Alignment of tetrads at the metaphase plate
3. Separation of sister chromatids
4. Separation of the homologs; no uncoupling of the centromere
5. Synapsis; chromosomes moving to the middle of the cell in pairs
-When homologous chromosomes crossover, what occurs?

Accepted Answer

A)  Two chromatids get tangled, resulting in one re-sequencing its DNA. 
B)  Two sister chromatids exchange identical pieces of DNA. 
C)  Specific proteins break the two strands and re-join them with their homologs. 
D)  Each of the four DNA strands of a tetrad is broken and the pieces are mixed. 
E)  Maternal alleles are "corrected" to be like paternal alleles and vice versa. 
A)  Two chromatids get tangled, resulting in one re-sequencing its DNA. 
B)  Two sister chromatids exchange identical pieces of DNA. 
C)  Specific proteins break the two strands and re-join them with their homologs. 
D)  Each of the four DNA strands of a tetrad is broken and the pieces are mixed. 
E)  Maternal alleles are "corrected" to be like paternal alleles and vice versa.

Question 10

Eukaryotic sexual life cycles show tremendous variation. Of the following elements, which do all sexual life cycles have in common?
I.Alternation of generations
II.Meiosis
III.Fertilization
IV.Gametes
V.Spores

Accepted Answer

A)  I, IV, and V 
B)  I, II, and IV 
C)  II, III, and IV 
D)  II, IV, and V 
E)  I, II, III, IV, and V 
A)  I, IV, and V 
B)  I, II, and IV 
C)  II, III, and IV 
D)  II, IV, and V 
E)  I, II, III, IV, and V

Question 11

Refer to the life cycles illustrated in Figure 13.1 to answer the following questions.
   
Figure 13.1
-In part III of Figure 13.1, the progression of events corresponds to which of the following series?

Accepted Answer

A)  zygote, mitosis, gametophyte, mitosis, fertilization, zygote, mitosis 
B)  sporophyte, meiosis, spore, mitosis, gametophyte, mitosis, gametes, fertilization 
C)  fertilization, mitosis, multicellular haploid, mitosis, spores, sporophyte 
D)  gametophyte, meiosis, zygote, spores, sporophyte, zygote 
E)  meiosis, fertilization, zygote, mitosis, adult, meiosis 
A)  zygote, mitosis, gametophyte, mitosis, fertilization, zygote, mitosis 
B)  sporophyte, meiosis, spore, mitosis, gametophyte, mitosis, gametes, fertilization 
C)  fertilization, mitosis, multicellular haploid, mitosis, spores, sporophyte 
D)  gametophyte, meiosis, zygote, spores, sporophyte, zygote 
E)  meiosis, fertilization, zygote, mitosis, adult, meiosis

Question 12

Use the following information to answer the next questions.
There is a group of invertebrate animals called rotifers, among which a particular group of species reproduces, as far as is known, only asexually. These rotifers, however, have survived a long evolutionary history without evidence of having been overcome by excessive mutations.
-Assuming that the eggs are diploid, tetraploid, or partially tetraploid, what mechanism may still occur without fertilization?

Accepted Answer

A)  meiosis in each generation 
B)  meiosis in every second generation 
C)  independent assortment of maternal and paternal chromosomes 
D)  meiosis in times of adverse environmental conditions 
E)  crossing over of homologs 
A)  meiosis in each generation 
B)  meiosis in every second generation 
C)  independent assortment of maternal and paternal chromosomes 
D)  meiosis in times of adverse environmental conditions 
E)  crossing over of homologs

Question 13

The somatic cells of a privet shrub each contain 46 chromosomes. To be as different as they are from human cells, which have the same number of chromosomes, which of the following must be true?

Accepted Answer

A)  Privet cells cannot reproduce sexually. 
B)  Privet sex cells have chromosomes that can synapse with human chromosomes in the laboratory. 
C)  Genes of privet chromosomes are significantly different than those in humans. 
D)  Privet shrubs must be metabolically more like animals than like other shrubs. 
E)  Genes on a particular privet chromosome, such as the X, must be on a different human chromosome, such as number 18. 
A)  Privet cells cannot reproduce sexually. 
B)  Privet sex cells have chromosomes that can synapse with human chromosomes in the laboratory. 
C)  Genes of privet chromosomes are significantly different than those in humans. 
D)  Privet shrubs must be metabolically more like animals than like other shrubs. 
E)  Genes on a particular privet chromosome, such as the X, must be on a different human chromosome, such as number 18.

Question 14

Which of the following might result in a human zygote with 45 chromosomes?

Accepted Answer

A)  an error in either egg or sperm meiotic anaphase 
B)  failure of the egg nucleus to be fertilized by the sperm 
C)  fertilization of a 23 chromosome human egg by a 22 chromosome sperm of a closely related species 
D)  an error in the alignment of chromosomes on the metaphase plate 
E)  lack of chiasmata in prophase I 
A)  an error in either egg or sperm meiotic anaphase 
B)  failure of the egg nucleus to be fertilized by the sperm 
C)  fertilization of a 23 chromosome human egg by a 22 chromosome sperm of a closely related species 
D)  an error in the alignment of chromosomes on the metaphase plate 
E)  lack of chiasmata in prophase I

Question 15

If the DNA content of a diploid cell in the G₁ phase of the cell cycle is x, then the DNA content of a single cell at metaphase of meiosis II would be

Accepted Answer

A)  0.25x. 
B)  0.5x. 
C)  x. 
D)  2x. 
E)  4x. 
A)  0.25x. 
B)  0.5x. 
C)  x. 
D)  2x. 
E)  4x.

Question 16

A human cell containing 22 autosomes and a Y chromosome is

Accepted Answer

A)  a sperm. 
B)  an egg. 
C)  a zygote. 
D)  a somatic cell of a male. 
E)  a somatic cell of a female. 
A)  a sperm. 
B)  an egg. 
C)  a zygote. 
D)  a somatic cell of a male. 
E)  a somatic cell of a female.

Question 17

After telophase I of meiosis, the chromosomal makeup of each daughter cell is

Accepted Answer

A)  diploid, and the chromosomes are each composed of a single chromatid. 
B)  diploid, and the chromosomes are each composed of two chromatids. 
C)  haploid, and the chromosomes are each composed of a single chromatid. 
D)  haploid, and the chromosomes are each composed of two chromatids. 
E)  tetraploid, and the chromosomes are each composed of two chromatids. 
A)  diploid, and the chromosomes are each composed of a single chromatid. 
B)  diploid, and the chromosomes are each composed of two chromatids. 
C)  haploid, and the chromosomes are each composed of a single chromatid. 
D)  haploid, and the chromosomes are each composed of two chromatids. 
E)  tetraploid, and the chromosomes are each composed of two chromatids.

Question 18

How many different combinations of maternal and paternal chromosomes can be packaged in gametes made by an organism with a diploid number of 8 (2n = 8)?

Accepted Answer

A)  2 
B)  4 
C)  8 
D)  16 
E)  32 
A)  2 
B)  4 
C)  8 
D)  16 
E)  32

Question 19

If a horticulturist breeding gardenias succeeds in having a single plant with a particularly desirable set of traits, which of the following would be her most probable and efficient route to establishing a line of such plants?

Accepted Answer

A)  Backtrack through her previous experiments to obtain another plant with the same traits. 
B)  Breed this plant with another plant with much weaker traits. 
C)  Clone the plant asexually to produce an identical one. 
D)  Force the plant to self-pollinate to obtain an identical one. 
E)  Add nitrogen to the soil of the offspring of this plant so the desired traits continue. 
A)  Backtrack through her previous experiments to obtain another plant with the same traits. 
B)  Breed this plant with another plant with much weaker traits. 
C)  Clone the plant asexually to produce an identical one. 
D)  Force the plant to self-pollinate to obtain an identical one. 
E)  Add nitrogen to the soil of the offspring of this plant so the desired traits continue.

Question 20

Which life cycle stage is found in plants but not animals?

Accepted Answer

A)  gamete 
B)  zygote 
C)  multicellular diploid 
D)  multicellular haploid 
E)  unicellular diploid 
A)  gamete 
B)  zygote 
C)  multicellular diploid 
D)  multicellular haploid 
E)  unicellular diploid

Exam 13: Meiosis and Sexual Life Cycles

Which of these statements is false?

The karyotype of one species of primate has 48 chromosomes. In a particular female, cell division goes awry and she produces one of her eggs with an extra chromosome (25). The most probable source of this error would be a mistake in which of the following?

How is natural selection related to sexual reproduction as opposed to asexual reproduction?

Refer to the life cycles illustrated in Figure 13.1 to answer the following questions. Figure 13.1 -Which of the life cycles is typical for animals?

A triploid cell contains three sets of chromosomes. If a cell of a usually diploid species with 42 chromosomes per cell is triploid, this cell would be expected to have which of the following?

If an organism is diploid and a certain gene found in the organism has 18 known alleles (variants), then any given organism of that species can/must have which of the following?

Refer to the life cycles illustrated in Figure 13.1 to answer the following questions. Figure 13.1 -In a life cycle such as that shown in part III of Figure 13.1, if the zygote's chromosome number is 10, which of the following will be true?

Eukaryotic sexual life cycles show tremendous variation. Of the following elements, which do all sexual life cycles have in common? I.Alternation of generations II.Meiosis III.Fertilization IV.Gametes V.Spores

Refer to the life cycles illustrated in Figure 13.1 to answer the following questions. Figure 13.1 -In part III of Figure 13.1, the progression of events corresponds to which of the following series?

The somatic cells of a privet shrub each contain 46 chromosomes. To be as different as they are from human cells, which have the same number of chromosomes, which of the following must be true?

Which of the following might result in a human zygote with 45 chromosomes?

If the DNA content of a diploid cell in the G₁ phase of the cell cycle is x, then the DNA content of a single cell at metaphase of meiosis II would be

A human cell containing 22 autosomes and a Y chromosome is

After telophase I of meiosis, the chromosomal makeup of each daughter cell is

How many different combinations of maternal and paternal chromosomes can be packaged in gametes made by an organism with a diploid number of 8 (2n = 8)?

If a horticulturist breeding gardenias succeeds in having a single plant with a particularly desirable set of traits, which of the following would be her most probable and efficient route to establishing a line of such plants?

Which life cycle stage is found in plants but not animals?

Introduction: Themes in the Study of Life

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

The Cell Cycle

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Regulation of Gene Expression

Viruses

Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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