Question 1

Identify the lagging strand during duplication of DNA starting from a double helix in the accompanying figure.

Accepted Answer

A)  a 
B)  b 
C)  c 
D)  d 
A)  a 
B)  b 
C)  c 
D)  d

Question 2

DNA is synthesized through a process known as ________.

Accepted Answer

A)  semiconservative replication 
B)  conservative replication 
C)  translation 
D)  transcription 
A)  semiconservative replication 
B)  conservative replication 
C)  translation 
D)  transcription

Question 3

What is a major difference between eukaryotic DNA replication and prokaryotic DNA replication?

Accepted Answer

A)  Prokaryotic replication does not require a primer. 
B)  Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have multiple origins of replication. 
C)  DNA replication in prokaryotic cells is conservative. DNA replication in eukaryotic cells is semiconservative. 
D)  DNA polymerases of prokaryotes can add nucleotides to both 3' and 5' ends of DNA strands; those of eukaryotes function only in the 5' → 3' direction. 
A)  Prokaryotic replication does not require a primer. 
B)  Prokaryotic chromosomes have a single origin of replication, whereas eukaryotic chromosomes have multiple origins of replication. 
C)  DNA replication in prokaryotic cells is conservative. DNA replication in eukaryotic cells is semiconservative. 
D)  DNA polymerases of prokaryotes can add nucleotides to both 3' and 5' ends of DNA strands; those of eukaryotes function only in the 5' → 3' direction.

Question 4

Use the following information to answer the question below.
The herpes viruses are important enveloped DNA viruses that cause disease in vertebrates and in some invertebrates such as oysters. Some of the human forms are herpes simplex virus (HSV) types I and II, causing facial and genital lesions, and the varicella zoster virus (VSV), causing chicken pox and shingles. Each of these three actively infects nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can later reactivate, replicate again, and infect others.
In electron micrographs of HSV infection, it can be seen that the intact virus initially reacts with cell surface proteoglycans, then with specific receptors. This is later followed by viral capsids docking with nuclear pores. Afterward, the capsids go from being full to being "empty." Which of the following best fits these observations?

Accepted Answer

A)  Viral capsids are needed for the cell to become infected; only the capsids enter the nucleus. 
B)  The viral envelope is not required for infectivity, since the envelope does not enter the nucleus. 
C)  Only the genetic material of the virus is involved in the cell's infectivity and is injected like the genome of a phage. 
D)  The viral envelope mediates entry into the cell, the capsid mediates entry into the nuclear membrane, and the genome is all that enters the nucleus. 
E)  The viral capsid mediates entry into the cell, and only the genomic DNA enters the nucleus, where it may or may not replicate. 
A)  Viral capsids are needed for the cell to become infected; only the capsids enter the nucleus. 
B)  The viral envelope is not required for infectivity, since the envelope does not enter the nucleus. 
C)  Only the genetic material of the virus is involved in the cell's infectivity and is injected like the genome of a phage. 
D)  The viral envelope mediates entry into the cell, the capsid mediates entry into the nuclear membrane, and the genome is all that enters the nucleus. 
E)  The viral capsid mediates entry into the cell, and only the genomic DNA enters the nucleus, where it may or may not replicate.

Question 5

Refer to the figure associated with this question. What bases will be added to the primer as DNA replication proceeds? The bases should appear in the new strand in the order that they will be added starting at the 3' end of the primer.

Accepted Answer

A)  C, A, G, C, A, G, A 
B)  T, C, T, G, C, T, G 
C)  A, G, A, C, G, A, C 
D)  G, T, C, G, T, C, T 
A)  C, A, G, C, A, G, A 
B)  T, C, T, G, C, T, G 
C)  A, G, A, C, G, A, C 
D)  G, T, C, G, T, C, T

Question 6

Telomere shortening puts a limit on the number of times a cell can divide. Research has shown that telomerase can extend the life span of cultured human cells. How might adding telomerase affect cellular aging?

Accepted Answer

A)  Telomerase will speed up the rate of cell proliferation. 
B)  Telomerase eliminates telomere shortening and retards aging. 
C)  Telomerase shortens telomeres, which delays cellular aging. 
D)  Telomerase would have no effect on cellular aging. 
A)  Telomerase will speed up the rate of cell proliferation. 
B)  Telomerase eliminates telomere shortening and retards aging. 
C)  Telomerase shortens telomeres, which delays cellular aging. 
D)  Telomerase would have no effect on cellular aging.

Question 7

In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts?

Accepted Answer

A)  DNA contains sulfur, whereas protein does not. 
B)  DNA contains phosphorus, whereas protein does not. 
C)  DNA contains nitrogen, whereas protein does not. 
D)  DNA contains purines, whereas protein includes pyrimidines. 
E)  RNA includes ribose, whereas DNA includes deoxyribose sugars. 
A)  DNA contains sulfur, whereas protein does not. 
B)  DNA contains phosphorus, whereas protein does not. 
C)  DNA contains nitrogen, whereas protein does not. 
D)  DNA contains purines, whereas protein includes pyrimidines. 
E)  RNA includes ribose, whereas DNA includes deoxyribose sugars.

Question 8

E. coli cells grown on 15N medium are transferred to 14N medium and allowed to grow for two more generations (two rounds of DNA replication). DNA extracted from these cells is centrifuged. What density distribution of DNA would you expect in this experiment?

Accepted Answer

A)  one high-density and one low-density band 
B)  one intermediate-density band 
C)  one high-density and one intermediate-density band 
D)  one low-density and one intermediate-density band 
E)  one low-density band 
A)  one high-density and one low-density band 
B)  one intermediate-density band 
C)  one high-density and one intermediate-density band 
D)  one low-density and one intermediate-density band 
E)  one low-density band

Question 9

In the accompanying figure, which structure causes the two strands of DNA to separate?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
A)  A 
B)  B 
C)  C 
D)  D

Question 10

In analyzing the number of different bases in a DNA sample, which result would be consistent with the base-pairing rules?

Accepted Answer

A)  A = G 
B)  A + G = C + T 
C)  A + T = G + T 
D)  A = C 
E)  G = T 
A)  A = G 
B)  A + G = C + T 
C)  A + T = G + T 
D)  A = C 
E)  G = T

Question 11

DNA contains the template needed to copy itself, but it has no catalytic activity in cells. What catalyzes the formation of phosphodiester bonds between adjacent nucleotides in the DNA polymer being formed?

Accepted Answer

A)  ribozymes 
B)  DNA polymerase 
C)  ATP 
D)  deoxyribonucleotide triphosphates 
A)  ribozymes 
B)  DNA polymerase 
C)  ATP 
D)  deoxyribonucleotide triphosphates

Exam 15: Dna and the Gene: Synthesis and Repair

Identify the lagging strand during duplication of DNA starting from a double helix in the accompanying figure.

DNA is synthesized through a process known as ________.

What is a major difference between eukaryotic DNA replication and prokaryotic DNA replication?

Refer to the figure associated with this question. What bases will be added to the primer as DNA replication proceeds? The bases should appear in the new strand in the order that they will be added starting at the 3' end of the primer.

Telomere shortening puts a limit on the number of times a cell can divide. Research has shown that telomerase can extend the life span of cultured human cells. How might adding telomerase affect cellular aging?

In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts?

E. coli cells grown on 15N medium are transferred to 14N medium and allowed to grow for two more generations (two rounds of DNA replication). DNA extracted from these cells is centrifuged. What density distribution of DNA would you expect in this experiment?

In the accompanying figure, which structure causes the two strands of DNA to separate?

In analyzing the number of different bases in a DNA sample, which result would be consistent with the base-pairing rules?

DNA contains the template needed to copy itself, but it has no catalytic activity in cells. What catalyzes the formation of phosphodiester bonds between adjacent nucleotides in the DNA polymer being formed?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Ecosystems and Global Ecology

Lipids, Membranes, and the First Cells

Inside the Cell

Energy and Enzymes: an Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cellcell Interactions

The Cell Cycle

Meiosis

Mendel and the Gene

How Genes Work

Transcription, Rna Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

The Molecular Revolution: Biotechnology and Beyond

Genes, Development, and Evolution

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, Signals, and Responses

Plant Reproduction and Development

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Animal Nervous Systems

Animal Sensory Systems

Animal Movement

Chemical Signals in Animals

Animal Reproduction and Development

The Immune System in Animals

An Introduction to Ecology

Behavioral Ecology

Population Ecology

Community Ecology

Biodiversity and Conservation Biology

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