Question 1

Colchicine interferes with the function of

Accepted Answer

A) microtubules. 
B) ribosomes. 
C) centrioles. 
D) centromeres. 
E) chromosomes. 
A) microtubules. 
B) ribosomes. 
C) centrioles. 
D) centromeres. 
E) chromosomes.

Question 2

Which is NOT a chromosomal abnormality?

Accepted Answer

A) deletion 
B) extra chromosomes 
C) translocation 
D) crossing over 
E) inversion 
A) deletion 
B) extra chromosomes 
C) translocation 
D) crossing over 
E) inversion

Question 3

With respect to chromosomes, the difference between normal human males and females is defined by which of the following?

Accepted Answer

A) In females, one X is deleted. 
B) Females possess one X and one Y. 
C) Males possess an X and a Y. 
D) Females have three Xs. 
E) Males have two Xs and a Y. 
A) In females, one X is deleted. 
B) Females possess one X and one Y. 
C) Males possess an X and a Y. 
D) Females have three Xs. 
E) Males have two Xs and a Y.

Question 4

Phenotypic treatments for genetic disorders include

Accepted Answer

A) preventing the disorders in the carriers. 
B) eliminating the defective gene. 
C) preventing a disorder from being passed on. 
D) preventing a disorder from being expressed. 
E) all of these. 
A) preventing the disorders in the carriers. 
B) eliminating the defective gene. 
C) preventing a disorder from being passed on. 
D) preventing a disorder from being expressed. 
E) all of these.

Question 5

Which chemical is used to keep chromosomes from separating during metaphase?

Accepted Answer

A) Giemsa stain 
B) acetone 
C) colchicine 
D) alcohol 
E) formaldehyde 
A) Giemsa stain 
B) acetone 
C) colchicine 
D) alcohol 
E) formaldehyde

Question 6

Concerning the sex chromosomes, which of the following is correct?

Accepted Answer

A) The Y chromosome carries a greater number of genes for nonsexual traits than does the X. 
B) X and Y are different in size but carry nearly equal numbers of genes. 
C) The X chromosome carries more genes for nonsexual traits than does the Y. 
D) The X chromosome carries only gender-related genes. 
E) The X chromosome carries the SRY gene. 
A) The Y chromosome carries a greater number of genes for nonsexual traits than does the X. 
B) X and Y are different in size but carry nearly equal numbers of genes. 
C) The X chromosome carries more genes for nonsexual traits than does the Y. 
D) The X chromosome carries only gender-related genes. 
E) The X chromosome carries the SRY gene.

Question 7

A color-blind man and a woman with normal vision whose father was color blind have a son.Color blindness, in this case, is caused by an X-linked recessive gene.If only the male offspring are considered, the probability that their son is color blind is

Accepted Answer

A) 0.25 (or 25%). 
B) 0.50 (or 50%). 
C) 0.75 (or 75%). 
D) 1.00 (or 100%). 
E) none of these. 
A) 0.25 (or 25%). 
B) 0.50 (or 50%). 
C) 0.75 (or 75%). 
D) 1.00 (or 100%). 
E) none of these.

Question 8

Amniocentesis is

Accepted Answer

A) a surgical means of repairing deformities. 
B) a form of chemotherapy that modifies or inhibits gene expression or the function of gene products. 
C) used in prenatal diagnosis to detect chromosomal mutations and metabolic disorders in embryos. 
D) a form of gene replacement therapy. 
E) all of these. 
A) a surgical means of repairing deformities. 
B) a form of chemotherapy that modifies or inhibits gene expression or the function of gene products. 
C) used in prenatal diagnosis to detect chromosomal mutations and metabolic disorders in embryos. 
D) a form of gene replacement therapy. 
E) all of these.

Question 9

If nondisjunction occurs during meiosis I,

Accepted Answer

A) the resulting sex cells are heterogametes. 
B) one-half of the resulting cells are n + 1, and the other half are n - 1. 
C) diploid cells are produced. 
D) all gametes will lack a chromosome and be infertile. 
E) only one half the gametes are affected. 
A) the resulting sex cells are heterogametes. 
B) one-half of the resulting cells are n + 1, and the other half are n - 1. 
C) diploid cells are produced. 
D) all gametes will lack a chromosome and be infertile. 
E) only one half the gametes are affected.

Question 10

Which of the following designates a normal human male?

Accepted Answer

A) YY 
B) XX 
C) XY 
D) XO 
E) XYY 
A) YY 
B) XX 
C) XY 
D) XO 
E) XYY

Question 11

Which of the following is a transfer of genes between non-homologous 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 12

Males tend to be affected in greater numbers by X-linked recessive genetic disorders than are females because

Accepted Answer

A) females have two dominant genes for the disorder. 
B) males have only one X chromosome. 
C) males have a double dose of the gene. 
D) Y chromosomes are not as strong as X chromosomes. 
E) none of these. 
A) females have two dominant genes for the disorder. 
B) males have only one X chromosome. 
C) males have a double dose of the gene. 
D) Y chromosomes are not as strong as X chromosomes. 
E) none of these.

Question 13

Sex chromosomes

Accepted Answer

A) determine gender. 
B) vary from one sex to another. 
C) carry some genes that have nothing to do with sex. 
D) were unknown to Mendel. 
E) are all of these. 
A) determine gender. 
B) vary from one sex to another. 
C) carry some genes that have nothing to do with sex. 
D) were unknown to Mendel. 
E) are all of these.

Question 14

Down syndrome

Accepted Answer

A) is very rare. 
B) is inherited as an X-linked recessive condition. 
C) results in some degree of mental impairment. 
D) individuals have normal life expectancies. 
E) cannot be detected through prenatal diagnosis. 
A) is very rare. 
B) is inherited as an X-linked recessive condition. 
C) results in some degree of mental impairment. 
D) individuals have normal life expectancies. 
E) cannot be detected through prenatal diagnosis.

Question 15

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 16

If a study of several pedigrees demonstrates that two parents are normal but some of their children express a trait, then the trait is controlled by a

Accepted Answer

A) codominant gene. 
B) simple dominant gene. 
C) recessive gene. 
D) sex-linked gene. 
E) No conclusion can be drawn. 
A) codominant gene. 
B) simple dominant gene. 
C) recessive gene. 
D) sex-linked gene. 
E) No conclusion can be drawn.

Question 17

Gene duplications

Accepted Answer

A) have proved to be adaptive in some cases. 
B) have resulted in many slightly different hemoglobin molecules in primates. 
C) always have negative consequences. 
D) can occur via unequal crossovers at prophase I. 
E) are all of these EXCEPT "always have negative consequences." 
A) have proved to be adaptive in some cases. 
B) have resulted in many slightly different hemoglobin molecules in primates. 
C) always have negative consequences. 
D) can occur via unequal crossovers at prophase I. 
E) are all of these EXCEPT "always have negative consequences."

Question 18

Galactosemia

Accepted Answer

A) is an X-linked recessive trait expressed more commonly in males. 
B) occurs more frequently in some ethnic groups than others. 
C) is an autosomal recessive inheritance. 
D) must be homozygous to be expressed. 
E) is an autosomal recessive inheritance and must be homozygous to be expressed. 
A) is an X-linked recessive trait expressed more commonly in males. 
B) occurs more frequently in some ethnic groups than others. 
C) is an autosomal recessive inheritance. 
D) must be homozygous to be expressed. 
E) is an autosomal recessive inheritance and must be homozygous to be expressed.

Question 19

In Down syndrome

Accepted Answer

A) as the age of the mother increases, the chance of the defect occurring in the unborn children increases. 
B) the influence of the father on the defect is equal to that of the mother. 
C) most embryos abort before complete term. 
D) a person with the defect cannot have a normal child. 
E) none of these are true. 
A) as the age of the mother increases, the chance of the defect occurring in the unborn children increases. 
B) the influence of the father on the defect is equal to that of the mother. 
C) most embryos abort before complete term. 
D) a person with the defect cannot have a normal child. 
E) none of these are true.

Question 20

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

Accepted Answer

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

Exam 12: Chromosomes and Human Inheritance

Colchicine interferes with the function of

Which is NOT a chromosomal abnormality?

With respect to chromosomes, the difference between normal human males and females is defined by which of the following?

Phenotypic treatments for genetic disorders include

Which chemical is used to keep chromosomes from separating during metaphase?

Concerning the sex chromosomes, which of the following is correct?

A color-blind man and a woman with normal vision whose father was color blind have a son.Color blindness, in this case, is caused by an X-linked recessive gene.If only the male offspring are considered, the probability that their son is color blind is

Amniocentesis is

If nondisjunction occurs during meiosis I,

Which of the following designates a normal human male?

Which of the following is a transfer of genes between non-homologous chromosomes?

Males tend to be affected in greater numbers by X-linked recessive genetic disorders than are females because

Sex chromosomes

Down syndrome

An X-linked carrier is a

If a study of several pedigrees demonstrates that two parents are normal but some of their children express a trait, then the trait is controlled by a

Gene duplications

Galactosemia

In Down syndrome

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

Invitation to Biology

Lifes Chemical Basis

Molecules of Life

Cell Structure and Function

A Closer Look at Cell Membranes

Ground Rules of Metabolism

Where It Startsphotosynthesis

Energy-Releasing Pathways

How Cells Reproduce

Meiosis and Sexual Reproduction

Observing Patterns in Inherited Traits

Dna Structure and Function

From Dna to Protein

Controls Over Genes

Recombinant Dna and Genetic Engineering

The Macroevolutionary Puzzle

Emergence of Evolutionary Thought

Organizing Information About Species

The Origin and Evolution of Life

Viruses and Prokaryotes

Protists the Simplest Eukaryotes

Plants

Fungi

Animals: the Invertebrates

Animal Evolution the Chordates

Human Evolution: a Case Study

Plant Tissues

Plant Nutrition and Transport

Plant Reproduction

Plant Growth and Development

Animal Tissues and Organ Systems

Neural Control

Sensory Perception

Endocrine Control

Protection, Support, and Movement

Circulation

Immunity

Respiration

Digestion and Human Nutrition

Maintaining the Internal Environment

Animal Reproductive Systems

Animal Development

Animal Behavior

Population Ecology

Community Structure and Biodiversity

Ecosystems

The Biosphere

Human Impacts on the Biosphere

Filters