Question 1

Which of the following processes is not a method of generating new combinations of alleles in the offspring of two individuals?

Accepted Answer

A)  crossing-over between chromosomes 
B)  fertilization of an egg by a sperm 
C)  independent assortment of chromosomes 
D)  linkage of genes 
A)  crossing-over between chromosomes 
B)  fertilization of an egg by a sperm 
C)  independent assortment of chromosomes 
D)  linkage of genes

Question 2

The "actual results" in the experiment depicted in the figure below differ significantly from the "expected results" predicted by Mendel's laws.  
This variation from the expected results probably occurs because the gene for body color and the gene for wing length

Accepted Answer

A)  are both recessive. 
B)  are close together on a single chromosome. 
C)  undergo independent assortment. 
D)  are located on completely opposite ends of the same chromosome. 
A)  are both recessive. 
B)  are close together on a single chromosome. 
C)  undergo independent assortment. 
D)  are located on completely opposite ends of the same chromosome.

Question 3

Which of the following statements would be true if the linkage between two traits were complete?

Accepted Answer

A)  Only the parental combinations of phenotypes could appear in the progeny. 
B)  The rules of independent assortment would hold true. 
C)  Combinations of phenotypes different from those seen in the parents would be produced. 
D)  The exchange of genetic material between chromosomes would be frequent. 
A)  Only the parental combinations of phenotypes could appear in the progeny. 
B)  The rules of independent assortment would hold true. 
C)  Combinations of phenotypes different from those seen in the parents would be produced. 
D)  The exchange of genetic material between chromosomes would be frequent.

Question 4

Why are X-linked recessive genetic disorders more commonly seen in males?

Accepted Answer

A)  For an X-linked disorder to occur, an individual must receive one allele only found on the X chromosome and a second allele found only on the Y chromosome, which females do not have. 
B)  Females must receive two copies of the recessive allele to exhibit the disorder, but males need only one copy. 
C)  The alleles of sex-linked genes are carried only on the Y chromosome, which females do not have. 
D)  Females only have X chromosomes and genes on the X chromosome are not expressed. 
A)  For an X-linked disorder to occur, an individual must receive one allele only found on the X chromosome and a second allele found only on the Y chromosome, which females do not have. 
B)  Females must receive two copies of the recessive allele to exhibit the disorder, but males need only one copy. 
C)  The alleles of sex-linked genes are carried only on the Y chromosome, which females do not have. 
D)  Females only have X chromosomes and genes on the X chromosome are not expressed.

Question 5

Chromosomes are composed of DNA and

Accepted Answer

A)  RNA. 
B)  alleles. 
C)  lipids. 
D)  proteins. 
A)  RNA. 
B)  alleles. 
C)  lipids. 
D)  proteins.

Question 6

The allele responsible for causing Huntington's disease is

Accepted Answer

A)  dominant. 
B)  recessive. 
C)  sex-linked. 
D)  not heritable. 
A)  dominant. 
B)  recessive. 
C)  sex-linked. 
D)  not heritable.

Question 7

Down syndrome results from trisomy of chromosome 21. Which of the following is not an example of how this may have happened?

Accepted Answer

A)  translocation of chromosome 21 
B)  failure of the homologous pair for chromosome 21 to separate in meiosis I 
C)  inversion of a portion of chromosome 21 during S phase 
D)  failure of the sister chromatids in a duplicated chromosome 21 to separate in meiosis II 
A)  translocation of chromosome 21 
B)  failure of the homologous pair for chromosome 21 to separate in meiosis I 
C)  inversion of a portion of chromosome 21 during S phase 
D)  failure of the sister chromatids in a duplicated chromosome 21 to separate in meiosis II

Question 8

For a genetic disorder caused by a dominant allele, individuals with which of the following genotypes would be affected?

Accepted Answer

A)  AA and aa 
B)  aa and Aa 
C)  AA and Aa 
D)  AA, Aa, and aa 
A)  AA and aa 
B)  aa and Aa 
C)  AA and Aa 
D)  AA, Aa, and aa

Question 9

All diseases are the result of inherited traits.

Accepted Answer

A) True 
 B)False

Question 10

The tendency to develop diseases, such as cancer and heart disease, is

Accepted Answer

A)  usually the result of a mutation in one gene. 
B)  the result of new combinations of alleles formed during meiosis. 
C)  the result of may genes and environmental factors. 
D)  the result of multiple mutations caused by crossing over. 
A)  usually the result of a mutation in one gene. 
B)  the result of new combinations of alleles formed during meiosis. 
C)  the result of may genes and environmental factors. 
D)  the result of multiple mutations caused by crossing over.

Question 11

The figure below is a pedigree for cystic fibrosis, an autosomal recessive disorder.  
Which of the following is true?

Accepted Answer

A)  At least one of the members of Generation 1 is a carrier of cystic fibrosis. 
B)  None of the members of Generation 2 is a carrier of cystic fibrosis. 
C)  Individual 2 in Generation 2 has cystic fibrosis. 
D)  The cystic fibrosis gene is found on a sex chromosome. 
A)  At least one of the members of Generation 1 is a carrier of cystic fibrosis. 
B)  None of the members of Generation 2 is a carrier of cystic fibrosis. 
C)  Individual 2 in Generation 2 has cystic fibrosis. 
D)  The cystic fibrosis gene is found on a sex chromosome.

Question 12

Examine the figure below of a pedigree that diagrams an X-linked gene.  
The genotype of the individual next to the question mark is

Accepted Answer

A)  heterozygous. 
B)  homozygous. 
C)  autosomal. 
D)  There is not enough information to determine the answer. 
A)  heterozygous. 
B)  homozygous. 
C)  autosomal. 
D)  There is not enough information to determine the answer.

Question 13

Which of the following genetic changes would not be heritable?

Accepted Answer

A)  a mutation in a skin cell 
B)  the loss of a chromosome in a sperm cell 
C)  the addition of a chromosome in an egg cell 
D)  a mutation in a gene in a gamete 
A)  a mutation in a skin cell 
B)  the loss of a chromosome in a sperm cell 
C)  the addition of a chromosome in an egg cell 
D)  a mutation in a gene in a gamete

Question 14

All organisms determine sex with X and Y chromosomes.

Accepted Answer

A) True 
 B)False

Question 15

A female who is a carrier of the sex-linked gene A has the genotype ________.

Accepted Answer

The answer of A female who is a carrier of...

Question 16

The chance that any two siblings will be genetically identical is astronomically small.

Accepted Answer

A) True 
 B)False

Question 17

Males with a recessive X-linked recessive allele that causes a disorder don't always show symptoms because they can also carry a dominant allele on their Y chromosome.

Accepted Answer

A) True 
 B)False

Question 18

A parent that is a carrier for the recessive autosomal disorder B has the genotype __________.

Accepted Answer

The answer of A parent that is a carrier for...

Question 19

In humans, which of the following chromosomes would probably carry the fewest genes?

Accepted Answer

A)  the Y chromosome 
B)  chromosome 4 
C)  the X chromosome 
D)  chromosome 14 
A)  the Y chromosome 
B)  chromosome 4 
C)  the X chromosome 
D)  chromosome 14

Question 20

An XX individual develops as a male. Which of the following statements offers the most likely explanation?

Accepted Answer

A)  This is the usual situation for an XX individual. 
B)  This occurs when the sperm does not contribute any genetic material. 
C)  A piece of a Y chromosome has become attached to one of the X chromosomes. 
D)  This occurs when the egg does not contribute any genetic material. 
A)  This is the usual situation for an XX individual. 
B)  This occurs when the sperm does not contribute any genetic material. 
C)  A piece of a Y chromosome has become attached to one of the X chromosomes. 
D)  This occurs when the egg does not contribute any genetic material.

Exam 11: Chromosomes and Human Genetics

Which of the following processes is not a method of generating new combinations of alleles in the offspring of two individuals?

The "actual results" in the experiment depicted in the figure below differ significantly from the "expected results" predicted by Mendel's laws. This variation from the expected results probably occurs because the gene for body color and the gene for wing length

Which of the following statements would be true if the linkage between two traits were complete?

Why are X-linked recessive genetic disorders more commonly seen in males?

Chromosomes are composed of DNA and

The allele responsible for causing Huntington's disease is

Down syndrome results from trisomy of chromosome 21. Which of the following is not an example of how this may have happened?

For a genetic disorder caused by a dominant allele, individuals with which of the following genotypes would be affected?

All diseases are the result of inherited traits.

The tendency to develop diseases, such as cancer and heart disease, is

The figure below is a pedigree for cystic fibrosis, an autosomal recessive disorder. Which of the following is true?

Examine the figure below of a pedigree that diagrams an X-linked gene. The genotype of the individual next to the question mark is

Which of the following genetic changes would not be heritable?

All organisms determine sex with X and Y chromosomes.

A female who is a carrier of the sex-linked gene A has the genotype ________.

The chance that any two siblings will be genetically identical is astronomically small.

Males with a recessive X-linked recessive allele that causes a disorder don't always show symptoms because they can also carry a dominant allele on their Y chromosome.

A parent that is a carrier for the recessive autosomal disorder B has the genotype __________.

In humans, which of the following chromosomes would probably carry the fewest genes?

An XX individual develops as a male. Which of the following statements offers the most likely explanation?

The Nature of Science and the Characteristics of Life

Organizing the Diversity of Life

Major Groups of Living Organisms

Chemical Building Blocks

Cell Structure and Internal Compartments

Cell Membranes, Transport, and Communication

Energy and Enzymes

Photosynthesis and Cellular Respiration

Cell Division

Patterns of Inheritance

DNA

From Gene to Protein

Control of Gene Expression

DNA Technology

How Evolution Works

Evolution of Populations

Adaptation and Speciation

The Evolutionary History of Life

Maintaining the Internal Environment

Animal Nutrition and Digestion

Gas Exchange

The Circulatory System

Animal Hormones

The Nervous System

Sensing the Environment

Skeletons, Muscles, and Movement

Defenses against Disease

Reproduction and Development

Animal Behavior

Plant Structure, Nutrition, and Transport

Plant Growth and Reproduction

The Biosphere

Growth of Populations

Interactions among Organisms

Communities of Organisms

Ecosystems

Global Change

Biodiversity and People

Cancer: Cell Division Out of Control

Harnessing the Human Genome

Humans and Evolution

Smoking--Beyond Lung Cancer

Feeding a Hungry Planet

Building a Sustainable Society

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