Question 1

What is an essential amino acid? Give an example.

Accepted Answer

An essential amino acid is one

Question 2

Which of the following is a sex-linked disorder?

Accepted Answer

A) Lesch-Nyhan syndrome 
B) Alkaptonuria 
C) Albinism 
D) Down syndrome 
E) Tay-Sachs disease 
A) Lesch-Nyhan syndrome 
B) Alkaptonuria 
C) Albinism 
D) Down syndrome 
E) Tay-Sachs disease

Question 3

You are a doctor who specializes in genetic diseases.A married couple comes to see you for genetic counseling.The woman has PKU,the symptoms of which she manages by diet.The man and woman are first cousins and would like to know the probability that any of their children will have the disease.What would you tell them?

Accepted Answer

Since the woman has the disease,she must

Question 4

Match between columns
                        Premises: Hypoglycemia
Lesch-Nyhan syndrome
Galactosemia
Tay-Sachs disease
Alkaptonuria

Accepted Answer

The Answer of Hexosaminidase A and Homogentisic acid oxidase and is...

Question 5

A mutation that has pleiotropic consequences

Accepted Answer

A) results in a single symptom in the affected person. 
B) may result in only slight symptoms in a person with the mutation. 
C) is only detected in homozygotes. 
D) has widespread consequences in the affected person. 
E) cannot be detected by enzyme assay. 
A) results in a single symptom in the affected person. 
B) may result in only slight symptoms in a person with the mutation. 
C) is only detected in homozygotes. 
D) has widespread consequences in the affected person. 
E) cannot be detected by enzyme assay.

Question 6

In people who do not have Tay-Sachs disease,the hexA gene encodes an enzyme that

Accepted Answer

A) converts purines to uric acid in the kidneys. 
B) removes a sugar group from phenylalanine. 
C) converts tyrosine to melanin in skin. 
D) cleaves acetylgalactosamine from gangliosides. 
E) synthesizes glycogen from glucose monomers. 
A) converts purines to uric acid in the kidneys. 
B) removes a sugar group from phenylalanine. 
C) converts tyrosine to melanin in skin. 
D) cleaves acetylgalactosamine from gangliosides. 
E) synthesizes glycogen from glucose monomers.

Question 7

The Guthrie test screens for excessive phenylalanine in the blood of infants.

Accepted Answer

A) True 
 B)False

Question 8

You discover a mutant strain of Neurospora crassa that will not grow on a minimal medium but that will grow on a medium supplemented by the amino acid methionine.How can you determine which step in the methionine synthesis pathway is affected by the mutation?

Accepted Answer

You would grow the strain on a series of

Question 9

How do scientists,lacking the ability to make controlled genetic crosses in humans,study the inheritance of and give genetic counseling on human genetic disorders?

Accepted Answer

Pedigree analysis can be done

Question 10

Because Lesch-Nyhan syndrome is a recessive X-linked disease,females who have an allele with the mutation responsible for this disease are generally symptom-free.

Accepted Answer

A) True 
 B)False

Question 11

Cystic fibrosis is an autosomal recessive disorder.What is the chance that two carrier parents will have an affected child?

Accepted Answer

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

Question 12

The sickle-cell mutant allele and wild-type β-globin allele are codominant.

Accepted Answer

A) True 
 B)False

Question 13

Explain the difference between the one-gene-one-enzyme hypothesis and the one-gene-one-polypeptide hypothesis.

Accepted Answer

A relationship is found between a mutati

Question 14

While the defective gene product in patients with PKU was identified using biochemical analysis,how was the cystic fibrosis gene identified?

Accepted Answer

The cystic fibrosis gene was identified

Question 15

A mutagen is

Accepted Answer

A) the process that generates mutants. 
B) the agent that induces mutants. 
C) the mutants that are generated by an agent. 
D) the experiment that generates mutants. 
E) the process that corrects mutants. 
A) the process that generates mutants. 
B) the agent that induces mutants. 
C) the mutants that are generated by an agent. 
D) the experiment that generates mutants. 
E) the process that corrects mutants.

Question 16

Albinism is caused by an inborn error of metabolism.

Accepted Answer

A) True 
 B)False

Question 17

A person with sickle-cell trait has ________ at the β-globin locus.

Accepted Answer

A) two wild-type alleles 
B) two mutant alleles 
C) one wild-type and one mutant allele 
D) one wild-type and one deleted allele 
E) one mutant and one deleted allele 
A) two wild-type alleles 
B) two mutant alleles 
C) one wild-type and one mutant allele 
D) one wild-type and one deleted allele 
E) one mutant and one deleted allele

Question 18

Auxotrophs are organisms that can grow

Accepted Answer

A) on minimal media. 
B) on complete media. 
C) only on amino acid supplemented media. 
D) only on vitamin supplemented media. 
E) on any media. 
A) on minimal media. 
B) on complete media. 
C) only on amino acid supplemented media. 
D) only on vitamin supplemented media. 
E) on any media.

Question 19

The cystic fibrosis gene (CFTR)codes for a protein that is essential for

Accepted Answer

A) secretion of mucus. 
B) ion transport across membranes. 
C) transport of oxygen in red blood cells. 
D) metabolism of certain amino acids. 
E) processing of gangliosides. 
A) secretion of mucus. 
B) ion transport across membranes. 
C) transport of oxygen in red blood cells. 
D) metabolism of certain amino acids. 
E) processing of gangliosides.

Question 20

What was the significance of Beadle and Tatum's experiment?

Accepted Answer

A) It resulted in the central dogma. 
B) It led to the discovery of bread mold. 
C) It resulted in the one-gene-one-enzyme hypothesis. 
D) It led to the discovery of the genetic code. 
E) It proved that X-rays were mutagens. 
A) It resulted in the central dogma. 
B) It led to the discovery of bread mold. 
C) It resulted in the one-gene-one-enzyme hypothesis. 
D) It led to the discovery of the genetic code. 
E) It proved that X-rays were mutagens.

Exam 4: Gene Function

What is an essential amino acid? Give an example.

Which of the following is a sex-linked disorder?

A mutation that has pleiotropic consequences

In people who do not have Tay-Sachs disease,the hexA gene encodes an enzyme that

The Guthrie test screens for excessive phenylalanine in the blood of infants.

You discover a mutant strain of Neurospora crassa that will not grow on a minimal medium but that will grow on a medium supplemented by the amino acid methionine.How can you determine which step in the methionine synthesis pathway is affected by the mutation?

How do scientists,lacking the ability to make controlled genetic crosses in humans,study the inheritance of and give genetic counseling on human genetic disorders?

Because Lesch-Nyhan syndrome is a recessive X-linked disease,females who have an allele with the mutation responsible for this disease are generally symptom-free.

Cystic fibrosis is an autosomal recessive disorder.What is the chance that two carrier parents will have an affected child?

The sickle-cell mutant allele and wild-type β-globin allele are codominant.

Explain the difference between the one-gene-one-enzyme hypothesis and the one-gene-one-polypeptide hypothesis.

While the defective gene product in patients with PKU was identified using biochemical analysis,how was the cystic fibrosis gene identified?

A mutagen is

Albinism is caused by an inborn error of metabolism.

A person with sickle-cell trait has ________ at the β-globin locus.

Auxotrophs are organisms that can grow

The cystic fibrosis gene (CFTR)codes for a protein that is essential for

What was the significance of Beadle and Tatum's experiment?

Genetics: An Introduction

DNA: The Genetic Material

DNA Replication

Gene Expression: Transcription

Gene Expression: Translation

Dna Mutation, DNA Repair, and Transposable Elements

Genomics: The Mapping and Sequencing of Genomes

Functional and Comparative Genomics

Recombinant DNA Technology

Mendelian Genetics

Chromosomal Basis of Inheritance

Extensions of and Deviations From Mendelian Genetic Principles

Genetic Mapping in Eukaryotes

Genetics of Bacteria and Bacteriophages

Variations in Chromosome Structure and Number

Regulation of Gene Expression in Bacteria and Bacteriophages

Regulation of Gene Expression in Eukaryotes

Genetic Analysis of Development

Genetics of Cancer

Population Genetics

Quantitative Genetics

Molecular Evolution

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