Question 1

In a pedigree chart, a female who does not demonstrate the trait being studied is represented by a

Accepted Answer

A)  darkened square. 
B)  clear diamond. 
C)  clear circle. 
D)  darkened triangle. 
E)  darkened oval. 
A)  darkened square. 
B)  clear diamond. 
C)  clear circle. 
D)  darkened triangle. 
E)  darkened oval.

Question 2

In human females, one of the sex chromosomes is switched off during early development in a phenomenon called

Accepted Answer

A)  karyotyping. 
B)  X inactivation. 
C)  X linkage. 
D)  crossing over. 
E)  SRY activation. 
A)  karyotyping. 
B)  X inactivation. 
C)  X linkage. 
D)  crossing over. 
E)  SRY activation.

Question 3

Pattern baldness is an example of a(n)

Accepted Answer

A)  sex-linked trait. 
B)  sex-influenced trait. 
C)  sex-limited trait. 
D)  sex-exclusive trait. 
E)  inactivation trait. 
A)  sex-linked trait. 
B)  sex-influenced trait. 
C)  sex-limited trait. 
D)  sex-exclusive trait. 
E)  inactivation trait.

Question 4

The enzyme missing in Tay-Sachs disease is

Accepted Answer

A)  cholinesterase. 
B)  hexosaminidase A. 
C)  neuraminidase. 
D)  hyaluronidase. 
E)  lactic dehydrogenase. 
A)  cholinesterase. 
B)  hexosaminidase A. 
C)  neuraminidase. 
D)  hyaluronidase. 
E)  lactic dehydrogenase.

Question 5

In Drosophila , a narrow, reduced eye is called a bar-eye. It is due to a dominant X-linked allele ( B ), while the full wild-type is due to the recessive gene ( B+ ). Give the F 1 and F 2 genotypic and phenotypic expectations of a cross of a homozygous wild-type female with a bar-eyed male.

Accepted Answer

B + B + x BY → F ₁: B + B wild

Question 6

Which of the following is a transfer of genes between nonhomologous chromosomes?

Accepted Answer

A)  crossing over 
B)  aneuploidy 
C)  trisomy 
D)  translocation 
E)  duplication 
A)  crossing over 
B)  aneuploidy 
C)  trisomy 
D)  translocation 
E)  duplication

Question 7

A genetic X-linked condition in which females exhibit patches of lighter and darker pigmented skin is

Accepted Answer

A)  psoriasis. 
B)  vitiligo. 
C)  ectodermal neoplasia. 
D)  hydrous ectodermal neoplasia. 
E)  incontinentia pigmenti. 
A)  psoriasis. 
B)  vitiligo. 
C)  ectodermal neoplasia. 
D)  hydrous ectodermal neoplasia. 
E)  incontinentia pigmenti.

Question 8

A carrier is a person who

Accepted Answer

A)  carries a recessive gene for a genetic disorder but shows no signs or symptoms. 
B)  shows signs and symptoms of a genetic disorder only under conditions of stress or other illness. 
C)  carries a gene for a genetic disorder and shows signs and symptoms most of the time. 
D)  carries a gene for a genetic disorder and shows signs and symptoms all of the time. 
E)  carries a gene for a genetic disorder and shows a reduced degree of signs and symptoms. 
A)  carries a recessive gene for a genetic disorder but shows no signs or symptoms. 
B)  shows signs and symptoms of a genetic disorder only under conditions of stress or other illness. 
C)  carries a gene for a genetic disorder and shows signs and symptoms most of the time. 
D)  carries a gene for a genetic disorder and shows signs and symptoms all of the time. 
E)  carries a gene for a genetic disorder and shows a reduced degree of signs and symptoms.

Question 9

The genetic disorder cri-du-chat syndrome is caused by

Accepted Answer

A)  inversion. 
B)  deletion. 
C)  duplication. 
D)  translocation. 
E)  aneuploidy. 
A)  inversion. 
B)  deletion. 
C)  duplication. 
D)  translocation. 
E)  aneuploidy.

Question 10

If gene replacement therapy became available

Accepted Answer

A)  it would not work for humans because we have too many chromosomes. 
B)  it would involve a surgical technique that separates chromosomes that have failed to segregate properly during meiosis II. 
C)  it could be used to treat victims of a recessive disease by removing the dominant damaging autosomal allele and replacing it with a harmless one. 
D)  it would replace defective alleles with normal ones. 
E)  it would remove entire chromosomes from cells and repair the defective genes. 
A)  it would not work for humans because we have too many chromosomes. 
B)  it would involve a surgical technique that separates chromosomes that have failed to segregate properly during meiosis II. 
C)  it could be used to treat victims of a recessive disease by removing the dominant damaging autosomal allele and replacing it with a harmless one. 
D)  it would replace defective alleles with normal ones. 
E)  it would remove entire chromosomes from cells and repair the defective genes.

Question 11

Because geneticists can't use human subjects for experimentation, a ____ is used to obtain an analysis of a genetic family history.

Accepted Answer

A)  blood test 
B)  hair sample. 
C)  tooth impression. 
D)  pedigree chart. 
E)  photograph analysis. 
A)  blood test 
B)  hair sample. 
C)  tooth impression. 
D)  pedigree chart. 
E)  photograph analysis.

Question 12

XXX females tend to

Accepted Answer

A)  have reproductive problems. 
B)  be slightly retarded. 
C)  have learning disabilities. 
D)  be sterile. 
E)  develop normally. 
A)  have reproductive problems. 
B)  be slightly retarded. 
C)  have learning disabilities. 
D)  be sterile. 
E)  develop normally.

Question 13

Match between columns
                        Premises: phenylketonuria
Down syndrome
Turner syndrome
hemophilia

Accepted Answer

The Answer of nondisjunction of the sex chromosomes and autosomal is...

Question 14

Which concept helps to explain why close relatives have a varied mix of genetic traits?

Accepted Answer

A)  segregation 
B)  dominance 
C)  incomplete dominance 
D)  independent assortment 
E)  codominance 
A)  segregation 
B)  dominance 
C)  incomplete dominance 
D)  independent assortment 
E)  codominance

Question 15

Which genetic change has yet to be linked to a disorder?

Accepted Answer

A)  inversion. 
B)  deletion. 
C)  duplication. 
D)  translocation. 
E)  aneuploidy. 
A)  inversion. 
B)  deletion. 
C)  duplication. 
D)  translocation. 
E)  aneuploidy.

Question 16

An X-linked carrier is a

Accepted Answer

A)  homozygous dominant female. 
B)  heterozygous female. 
C)  homozygous recessive female. 
D)  homozygous male. 
E)  heterozygous male. 
A)  homozygous dominant female. 
B)  heterozygous female. 
C)  homozygous recessive female. 
D)  homozygous male. 
E)  heterozygous male.

Question 17

Which of the following cannot be classified as a genetic disease?

Accepted Answer

A)  a genetic predisposition to develop an allergy 
B)  Huntington disease 
C)  sickle cell anemia 
D)  cystic fibrosis 
E)  sickle cell trait 
A)  a genetic predisposition to develop an allergy 
B)  Huntington disease 
C)  sickle cell anemia 
D)  cystic fibrosis 
E)  sickle cell trait

Question 18

Red-green color blindness is an X-linked recessive trait in humans. What is the probability that a color-blind woman and a man with normal vision will have a color-blind daughter?

Accepted Answer

A)  100 percent 
B)  75 percent 
C)  50 percent 
D)  25 percent 
E)  0 percent 
A)  100 percent 
B)  75 percent 
C)  50 percent 
D)  25 percent 
E)  0 percent

Question 19

The chromosome composition of 1 in 1,000 females is

Accepted Answer

A)  XO. 
B)  XX. 
C)  XXX. 
D)  XXY. 
E)  XYY. 
A)  XO. 
B)  XX. 
C)  XXX. 
D)  XXY. 
E)  XYY.

Question 20

Familial hypercholesterolemia is a condition explainable by

Accepted Answer

A)  autosomal dominance. 
B)  X linkage. 
C)  autosomal recessiveness. 
D)  translocation. 
E)  chromosomal duplication. 
A)  autosomal dominance. 
B)  X linkage. 
C)  autosomal recessiveness. 
D)  translocation. 
E)  chromosomal duplication.

Exam 20: Chromosomes and Human Genetics

In a pedigree chart, a female who does not demonstrate the trait being studied is represented by a

In human females, one of the sex chromosomes is switched off during early development in a phenomenon called

Pattern baldness is an example of a(n)

The enzyme missing in Tay-Sachs disease is

In Drosophila , a narrow, reduced eye is called a bar-eye. It is due to a dominant X-linked allele ( B ), while the full wild-type is due to the recessive gene ( B+ ). Give the F 1 and F 2 genotypic and phenotypic expectations of a cross of a homozygous wild-type female with a bar-eyed male.

Which of the following is a transfer of genes between nonhomologous chromosomes?

A genetic X-linked condition in which females exhibit patches of lighter and darker pigmented skin is

A carrier is a person who

The genetic disorder cri-du-chat syndrome is caused by

If gene replacement therapy became available

Because geneticists can't use human subjects for experimentation, a ____ is used to obtain an analysis of a genetic family history.

XXX females tend to

Which concept helps to explain why close relatives have a varied mix of genetic traits?

Which genetic change has yet to be linked to a disorder?

An X-linked carrier is a

Which of the following cannot be classified as a genetic disease?

Red-green color blindness is an X-linked recessive trait in humans. What is the probability that a color-blind woman and a man with normal vision will have a color-blind daughter?

The chromosome composition of 1 in 1,000 females is

Familial hypercholesterolemia is a condition explainable by

Learning About Human Biology

Chemistry of Life

Cells and How They Work

Tissues, Organs, and Organ Systems

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Circulation: the Heart and Blood Vessels

Blood

Immunity and Disease

The Respiratory System

Digestion and Nutrition

The Urinary System

The Nervous System

Sensory Systems

The Endocrine System

Reproductive Systems

Development and Aging

Cell Reproduction

Introduction to Genetics

DNA, Genes, and Biotechnology

Genes and Disease: Cancer

Principles of Evolution

Principles of Ecology

Human Impacts on the Biosphere

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In Drosophila , a narrow, reduced eye is called a bar-eye. It is due to a dominant X-linked allele ( B ), while the full wild-type is due to the recessive gene ( B+ ). Give the F ₁ and F ₂ genotypic and phenotypic expectations of a cross of a homozygous wild-type female with a bar-eyed male.