Question 1

In ______, a single gene has many different effects on the phenotype.

Accepted Answer

A) pleiotropy 
B) continuous variation 
C) epistasis 
D) polygenic inheritance 
E) incomplete dominance 
A) pleiotropy 
B) continuous variation 
C) epistasis 
D) polygenic inheritance 
E) incomplete dominance

Question 2

A translocation occurs when parts of two nonhomologous chromosomes are exchanged.

Accepted Answer

A) True 
 B)False

Question 3

The exchange of segments between nonhomologous chromosomes is called a(n):

Accepted Answer

A) deletion. 
B) inversion. 
C) duplication. 
D) translocation. 
E) point mutation. 
A) deletion. 
B) inversion. 
C) duplication. 
D) translocation. 
E) point mutation.

Question 4

A linkage map provides the approximate positions of the genes on a chromosome.

Accepted Answer

A) True 
 B)False

Question 5

A nucleosome is composed of histone proteins wrapped around a DNA filament.

Accepted Answer

A) True 
 B)False

Question 6

Which of the following statements about transposons is FALSE?

Accepted Answer

A) They are also called "jumping genes." 
B) They are movable genetic elements. 
C) They may lead to mutation. 
D) Plasmids can function as transposons. 
E) They occur only in bacteria. 
A) They are also called "jumping genes." 
B) They are movable genetic elements. 
C) They may lead to mutation. 
D) Plasmids can function as transposons. 
E) They occur only in bacteria.

Question 7

The seeds of all the progeny of a cross between yellow-seeded plants and green-seeded plants are as yellow as those of the yellow-seeded parent.From this information, it is clear that:

Accepted Answer

A) this is an example of a dihybrid cross. 
B) the F1 generation consists entirely of yellow-seeded plants. 
C) the F2 generation consists entirely of yellow-seeded plants. 
D) green is a dominant characteristic. 
E) yellow is a recessive characteristic. 
A) this is an example of a dihybrid cross. 
B) the F1 generation consists entirely of yellow-seeded plants. 
C) the F2 generation consists entirely of yellow-seeded plants. 
D) green is a dominant characteristic. 
E) yellow is a recessive characteristic.

Question 8

Which of the following statements about sexual reproduction is FALSE?

Accepted Answer

A) It occurs only in eukaryotic organisms. 
B) It is necessary for the survival of the population. 
C) It involves a regular alternation between meiosis and fertilization. 
D) It produces and maintains an infinite array of genetic diversity in populations. 
E) It provides the basic mechanism of evolution. 
A) It occurs only in eukaryotic organisms. 
B) It is necessary for the survival of the population. 
C) It involves a regular alternation between meiosis and fertilization. 
D) It produces and maintains an infinite array of genetic diversity in populations. 
E) It provides the basic mechanism of evolution.

Question 9

When the phenotype of a heterozygote is intermediate between the phenotypes of its homozygous parents, the condition is known as:

Accepted Answer

A) pleiotropy. 
B) aneuploidy. 
C) epistasis. 
D) polygenic inheritance. 
E) incomplete dominance. 
A) pleiotropy. 
B) aneuploidy. 
C) epistasis. 
D) polygenic inheritance. 
E) incomplete dominance.

Question 10

Cytoplasmic inheritance in plants involves genes present in the:

Accepted Answer

A) cytosol only. 
B) plastids only. 
C) mitochondria only. 
D) cytosol and plastids. 
E) mitochondria and plastids. 
A) cytosol only. 
B) plastids only. 
C) mitochondria only. 
D) cytosol and plastids. 
E) mitochondria and plastids.

Question 11

Which of the following statements about homologous chromosomes is FALSE?

Accepted Answer

A) Both homologs are present in a zygote. 
B) One homolog comes from one parent and the other homolog from the other parent. 
C) Homologs resemble each other in the kinds of hereditary information they contain. 
D) Homologs resemble each other in size but not in shape. 
E) Homologs constitute a member of a pair. 
A) Both homologs are present in a zygote. 
B) One homolog comes from one parent and the other homolog from the other parent. 
C) Homologs resemble each other in the kinds of hereditary information they contain. 
D) Homologs resemble each other in size but not in shape. 
E) Homologs constitute a member of a pair.

Question 12

The pairing of homologous chromosomes is called:

Accepted Answer

A) synapsis. 
B) chiasma. 
C) crossing-over. 
D) recombination. 
E) bivalence. 
A) synapsis. 
B) chiasma. 
C) crossing-over. 
D) recombination. 
E) bivalence.

Question 13

Which of the following statements concerning histones is FALSE?

Accepted Answer

A) They are responsible for the folding of DNA. 
B) They are present in four distinct types. 
C) They are always present in chromatin. 
D) They are synthesized during the S phase of the cell cycle. 
E) They are positively charged. 
A) They are responsible for the folding of DNA. 
B) They are present in four distinct types. 
C) They are always present in chromatin. 
D) They are synthesized during the S phase of the cell cycle. 
E) They are positively charged.

Question 14

Nuclear envelopes form around single-stranded chromosomes during:

Accepted Answer

A) telophase II. 
B) metaphase I. 
C) prophase I. 
D) telophase I. 
E) metaphase II. 
A) telophase II. 
B) metaphase I. 
C) prophase I. 
D) telophase I. 
E) metaphase II.

Question 15

In peas, the dominant alleles A and B must be present for purple flower pigment to be produced; otherwise the flowers are white.What offspring would you expect from a cross between plants of genotypes Aabb and aaBb?

Accepted Answer

A) one purple: three white 
B) three purple: one white 
C) one purple: one white 
D) nine purple: two white 
E) two purple: three white 
A) one purple: three white 
B) three purple: one white 
C) one purple: one white 
D) nine purple: two white 
E) two purple: three white

Question 16

Suppose that a plant has two genes that are linked, with Ab on one homolog of a homologous pair of chromosomes and aB on the other homolog.What gametes could the plant produce if crossing-over occurred between these genes during meiosis?

Accepted Answer

A) Ab and aB only 
B) AB and ab only 
C) Aa and Bb only 
D) Ab, aB, AB, and ab only 
E) Ab, aB, AB, ab, Aa, and Bb only 
A) Ab and aB only 
B) AB and ab only 
C) Aa and Bb only 
D) Ab, aB, AB, and ab only 
E) Ab, aB, AB, ab, Aa, and Bb only

Question 17

Which of the following is true of Mendel's second law but not his first law?

Accepted Answer

A) The two alleles of a gene assort independently of the alleles of the other genes. 
B) The two alleles of a gene separate from each other during the formation of gametes. 
C) A plant heterozygous for a trait forms more gametes than a plant homozygous for that trait. 
D) A plant homozygous for a trait forms more gametes than a plant heterozygous for that trait. 
E) Alleles occupy the same locus on homologous chromosomes. 
A) The two alleles of a gene assort independently of the alleles of the other genes. 
B) The two alleles of a gene separate from each other during the formation of gametes. 
C) A plant heterozygous for a trait forms more gametes than a plant homozygous for that trait. 
D) A plant homozygous for a trait forms more gametes than a plant heterozygous for that trait. 
E) Alleles occupy the same locus on homologous chromosomes.

Question 18

Which of the following statements about alleles is FALSE?

Accepted Answer

A) They are different forms of the same gene. 
B) Interactions between alleles determine the characteristics of diploid organisms. 
C) They occupy different sites on homologous chromosomes. 
D) The site of an allele is called its locus. 
E) Dominant alleles are represented by uppercase letters, recessive alleles by lowercase letters. 
A) They are different forms of the same gene. 
B) Interactions between alleles determine the characteristics of diploid organisms. 
C) They occupy different sites on homologous chromosomes. 
D) The site of an allele is called its locus. 
E) Dominant alleles are represented by uppercase letters, recessive alleles by lowercase letters.

Question 19

Which of the following is NOT a possible cause of maternal inheritance?

Accepted Answer

A) The generative cell receives neither plastids nor mitochondria from the microspore. 
B) The generative cell receives plastids and mitochondria but they degenerate. 
C) Plastids and mitochondria are excluded from generative and sperm cells. 
D) Plastids and mitochondria are present in sperm cells but are not transmitted into the egg. 
E) Plastids and mitochondria are present in sperm cells but only plastids are transmitted into the egg. 
A) The generative cell receives neither plastids nor mitochondria from the microspore. 
B) The generative cell receives plastids and mitochondria but they degenerate. 
C) Plastids and mitochondria are excluded from generative and sperm cells. 
D) Plastids and mitochondria are present in sperm cells but are not transmitted into the egg. 
E) Plastids and mitochondria are present in sperm cells but only plastids are transmitted into the egg.

Question 20

If a cell has three pairs of homologous chromosomes, in how many ways could they be distributed among the haploid cells produced by meiosis?

Accepted Answer

A) two 
B) three 
C) four 
D) eight 
E) nine 
A) two 
B) three 
C) four 
D) eight 
E) nine

Exam 8: Sexual Reproduction and Heredity

In ______, a single gene has many different effects on the phenotype.

A translocation occurs when parts of two nonhomologous chromosomes are exchanged.

The exchange of segments between nonhomologous chromosomes is called a(n):

A linkage map provides the approximate positions of the genes on a chromosome.

A nucleosome is composed of histone proteins wrapped around a DNA filament.

Which of the following statements about transposons is FALSE?

The seeds of all the progeny of a cross between yellow-seeded plants and green-seeded plants are as yellow as those of the yellow-seeded parent.From this information, it is clear that:

Which of the following statements about sexual reproduction is FALSE?

When the phenotype of a heterozygote is intermediate between the phenotypes of its homozygous parents, the condition is known as:

Cytoplasmic inheritance in plants involves genes present in the:

Which of the following statements about homologous chromosomes is FALSE?

The pairing of homologous chromosomes is called:

Which of the following statements concerning histones is FALSE?

Nuclear envelopes form around single-stranded chromosomes during:

In peas, the dominant alleles A and B must be present for purple flower pigment to be produced; otherwise the flowers are white.What offspring would you expect from a cross between plants of genotypes Aabb and aaBb?

Suppose that a plant has two genes that are linked, with Ab on one homolog of a homologous pair of chromosomes and aB on the other homolog.What gametes could the plant produce if crossing-over occurred between these genes during meiosis?

Which of the following is true of Mendel's second law but not his first law?

Which of the following statements about alleles is FALSE?

Which of the following is NOT a possible cause of maternal inheritance?

If a cell has three pairs of homologous chromosomes, in how many ways could they be distributed among the haploid cells produced by meiosis?

Botany: an Introduction

The Molecular Composition of Plant Cells

The Plant Cell and the Cell Cycle

The Movement of Substances Into and Out of Cells

The Flow of Energy

Respiration

Photosynthesis, Light, and Life

The Chemistry of Heredity and Gene Expression

Recombinant Dna Technology, Plant Biotechnology, and Genomics

The Process of Evolution

Systematics: the Science of Biological Diversity

Prokaryotes and Viruses

Fungi

Protists: Algae and Heterotrophic Protists

Bryophytes

Seedless Vascular Plants

Gymnosperms

Introduction to the Angiosperms

Evolution of the Angiosperms

Plants and People

Early Development of the Plant Body

Cells and Tissues of the Plant Body

The Root: Structure and Development

The Shoot: Primary Structure and Development

Secondary Growth in Stems

Regulating Growth and Development: the Plant Hormones

External Factors and Plant Growth

Plant Nutrition and Soils

The Movement of Water and Solutes in Plants

The Dynamics of Communities and Ecosystems

Global Ecology

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