Question 1

During normal DNA replication, why is part of the DNA at the ends of linear chromosomes NOT copied into the new DNA strands?

Accepted Answer

A) because DNA ligase cannot join pieces at the end of a chromosome 
B) because RNA primers at the beginning of a new strand cannot be replaced with DNA 
C) because those ends are Okazaki fragments that are lost 
D) because cells do not need the DNA at the ends of chromosomes 
A) because DNA ligase cannot join pieces at the end of a chromosome 
B) because RNA primers at the beginning of a new strand cannot be replaced with DNA 
C) because those ends are Okazaki fragments that are lost 
D) because cells do not need the DNA at the ends of chromosomes

Question 2

Why does DNA replication proceed continuously on the leading strand and discontinuously on the lagging strand?

Accepted Answer

A) because DNA polymerase synthesizes DNA in only one direction 
B) because DNA ligase operates in only one direction 
C) because DNA polymerase contains more than one subunit 
D) because DNA polymerase synthesizes DNA in two directions 
A) because DNA polymerase synthesizes DNA in only one direction 
B) because DNA ligase operates in only one direction 
C) because DNA polymerase contains more than one subunit 
D) because DNA polymerase synthesizes DNA in two directions

Question 3

What type of charge do histones tend to carry?

Accepted Answer

A) a mixture of positive and negative charges 
B) no charge 
C) a negative charge 
D) a positive charge 
A) a mixture of positive and negative charges 
B) no charge 
C) a negative charge 
D) a positive charge

Question 4

Individuals with Xeroderma pigmentosum inherit a faulty DNA repair mechanism. How does this disorder manifest in a patient?

Accepted Answer

A) The patient is sterile. 
B) The Okazaki fragments produced during DNA replication cannot join. 
C) No proofreading occurs during DNA replication. 
D) The patient easily develops skin cancer when exposed to sunlight. 
A) The patient is sterile. 
B) The Okazaki fragments produced during DNA replication cannot join. 
C) No proofreading occurs during DNA replication. 
D) The patient easily develops skin cancer when exposed to sunlight.

Question 5

Which of the following describes the composition of a nucleotide?

Accepted Answer

A) a five-carbon sugar, a phosphate group, and one of four amino acids 
B) a five-carbon sugar, a nitrogenous base, and one of twenty amino acids 
C) a five-carbon sugar, a phosphate group, and one of four nitrogenous bases 
D) a six-carbon sugar, a phosphate group, and one of twenty amino acids 
A) a five-carbon sugar, a phosphate group, and one of four amino acids 
B) a five-carbon sugar, a nitrogenous base, and one of twenty amino acids 
C) a five-carbon sugar, a phosphate group, and one of four nitrogenous bases 
D) a six-carbon sugar, a phosphate group, and one of twenty amino acids

Question 6

Match each researcher or set of researchers with the discovery or experiment each is associated with.
-showed that DNA replication in Escherichia coli is semiconservative

Accepted Answer

A) Watson and Crick 
B) Avery, MacLeod, and McCarty 
C) Frederick Griffith 
D) Hershey and Chase 
E) Meselson and Stahl 
A) Watson and Crick 
B) Avery, MacLeod, and McCarty 
C) Frederick Griffith 
D) Hershey and Chase 
E) Meselson and Stahl

Question 7

Which nitrogenous bases are considered purines?

Accepted Answer

A) thymine and cytosine 
B) adenine and cytosine 
C) thymine and adenine 
D) adenine and guanine 
A) thymine and cytosine 
B) adenine and cytosine 
C) thymine and adenine 
D) adenine and guanine

Question 8

-In the figure, what does the structure labelled A represent?

Accepted Answer

A) single-stranded binding protein 
B) helicase 
C) DNA polymerase 
D) DNA ligase 
A) single-stranded binding protein 
B) helicase 
C) DNA polymerase 
D) DNA ligase

Question 9

Why is DNA replication said to be semiconservative?
a.because half of the DNA in a cell comes from one parent and half comes from the other parent
b.because the number of nucleotides within genes remains constant
c.because each new DNA molecule is composed of one old strand and one new strand
d.because the same process of DNA replication is used by all organisms

Accepted Answer

The answer of Why is DNA replication said to be...

Question 10

-Why do prokaryotic genomes not require telomerases?

Accepted Answer

A) because they are circular 
B) because they contain fewer genes 
C) because they are small 
D) because they are relatively simple 
A) because they are circular 
B) because they contain fewer genes 
C) because they are small 
D) because they are relatively simple

Question 11

How are the two strands in DNA's double helix held to each other?

Accepted Answer

A) by hydrophobic interactions 
B) by hydrogen bonds 
C) by ionic bonds 
D) by phosphodiester bonds 
A) by hydrophobic interactions 
B) by hydrogen bonds 
C) by ionic bonds 
D) by phosphodiester bonds

Question 12

In the Hershey and Chase experiment, why was the pellet radioactive after bacteria had been infected with 32P-labelled viruses and centrifuged?

Accepted Answer

A) The bacteria had incorporated radioactive proteins into their cell membranes. 
B) The virus particles had incorporated radioactive proteins from the bacterial DNA. 
C) The bacteria had incorporated radioactive DNA. 
D) The bacteria had incorporated radioactive proteins into their DNA. 
A) The bacteria had incorporated radioactive proteins into their cell membranes. 
B) The virus particles had incorporated radioactive proteins from the bacterial DNA. 
C) The bacteria had incorporated radioactive DNA. 
D) The bacteria had incorporated radioactive proteins into their DNA.

Question 13

Where are telomeres located?

Accepted Answer

A) within genes 
B) in the middle of chromosomes 
C) at the ends of a chromosome 
D) at replication origins 
A) within genes 
B) in the middle of chromosomes 
C) at the ends of a chromosome 
D) at replication origins

Question 14

Which of the following techniques did Wilkins and Franklin use to study the structure of DNA?

Accepted Answer

A) electron microscopy 
B) X-ray diffraction 
C) molecular scale models of nucleotides 
D) computer-assisted graphics 
A) electron microscopy 
B) X-ray diffraction 
C) molecular scale models of nucleotides 
D) computer-assisted graphics

Question 15

What closes nicks between DNA fragments, forming a covalent bond that ties or joins the fragments together?

Accepted Answer

A) DNA ligase 
B) helicase 
C) topoisomerase 
D) primase 
A) DNA ligase 
B) helicase 
C) topoisomerase 
D) primase

Question 16

Suppose you take a cell from an adult cow and attempt to produce a clone of that cow. Also suppose that, for some reason, telomerase is NOT functioning in that cell or in any cell that comes from it. What would you expect to happen with the clone?

Accepted Answer

A) The lack of telomerase should have no effect on the clone. 
B) When the clone grows up, it will most likely have cancer. 
C) The cell will never be able to divide at all. 
D) The cell may divide, but after a certain number of divisions, cell division will stop. 
A) The lack of telomerase should have no effect on the clone. 
B) When the clone grows up, it will most likely have cancer. 
C) The cell will never be able to divide at all. 
D) The cell may divide, but after a certain number of divisions, cell division will stop.

Question 17

What is the function of telomerase in humans?

Accepted Answer

A) to add telomere repeats in all human cells 
B) to add telomere repeats in some human cells 
C) to remove telomere repeats in all human cells 
D) to remove telomere repeats in some human cells 
A) to add telomere repeats in all human cells 
B) to add telomere repeats in some human cells 
C) to remove telomere repeats in all human cells 
D) to remove telomere repeats in some human cells

Question 18

How do DNA repair enzymes typically find mismatched base pairs?

Accepted Answer

A) by scanning for Okazaki fragments 
B) by scanning for distortions in the newly synthesized chain 
C) by scanning for missing hydrogen bonds 
D) by scanning for unsealed nicks in the DNA strands 
A) by scanning for Okazaki fragments 
B) by scanning for distortions in the newly synthesized chain 
C) by scanning for missing hydrogen bonds 
D) by scanning for unsealed nicks in the DNA strands

Question 19

Match each researcher or set of researchers with the discovery or experiment each is associated with.
-showed that the genetic material of bacteriophage T2 is DNA

Accepted Answer

A) Watson and Crick 
B) Avery, MacLeod, and McCarty 
C) Frederick Griffith 
D) Hershey and Chase 
E) Meselson and Stahl 
A) Watson and Crick 
B) Avery, MacLeod, and McCarty 
C) Frederick Griffith 
D) Hershey and Chase 
E) Meselson and Stahl

Question 20

What is the ultimate source of variability in offspring?

Accepted Answer

A) Okazaki fragments 
B) DNA repairs 
C) nucleosomes 
D) mutations 
A) Okazaki fragments 
B) DNA repairs 
C) nucleosomes 
D) mutations

Exam 12: Dna Structure, Replication, and Organization

During normal DNA replication, why is part of the DNA at the ends of linear chromosomes NOT copied into the new DNA strands?

Why does DNA replication proceed continuously on the leading strand and discontinuously on the lagging strand?

What type of charge do histones tend to carry?

Individuals with Xeroderma pigmentosum inherit a faulty DNA repair mechanism. How does this disorder manifest in a patient?

Which of the following describes the composition of a nucleotide?

Match each researcher or set of researchers with the discovery or experiment each is associated with. -showed that DNA replication in Escherichia coli is semiconservative

Which nitrogenous bases are considered purines?

-In the figure, what does the structure labelled A represent?

-Why do prokaryotic genomes not require telomerases?

How are the two strands in DNA's double helix held to each other?

In the Hershey and Chase experiment, why was the pellet radioactive after bacteria had been infected with 32P-labelled viruses and centrifuged?

Where are telomeres located?

Which of the following techniques did Wilkins and Franklin use to study the structure of DNA?

What closes nicks between DNA fragments, forming a covalent bond that ties or joins the fragments together?

Suppose you take a cell from an adult cow and attempt to produce a clone of that cow. Also suppose that, for some reason, telomerase is NOT functioning in that cell or in any cell that comes from it. What would you expect to happen with the clone?

What is the function of telomerase in humans?

How do DNA repair enzymes typically find mismatched base pairs?

Match each researcher or set of researchers with the discovery or experiment each is associated with. -showed that the genetic material of bacteriophage T2 is DNA

What is the ultimate source of variability in offspring?

Light and Life

The Cell: an Overview

Defining Life and Its Origins

Energy and Enzymes

Cell Membranes and Signalling

Cellular Respiration

Photosynthesis

Cell Cycles

Genetic Recombination

Mendel, Genes, and Inheritance

Genes, Chromosomes, and Human Genetics

Gene Structure and Expression

Control of Gene Expression

Dna Technologies

Genomes and Proteomes

Evolution: the Development of the Theory

Microevolution: Changes Within Populations

Species and Macroevolution

Understanding the History of Life on Earth

Humans and Evolution

Bacteria and Archaea

Viruses, Viroids, and Prions: Infectious Biological Particles

Protists

Fungi

Plants

Diversity of Animals 1: Sponges, Radiata, Platyhelminthes, and Protostomes

Diversity of Animals 2: Deuterostomes: Vertebrates and Their Closest Relatives

Population Ecology

Population Interactions and Community Ecology

Ecosystems

Conservation of Biodiversity

Putting Selection to Work

Organization of the Plant Body

Transport in Plants

Reproduction and Development in Flowering Plants

Plant Nutrition

Plant Signals and Responses to the Environment

Introduction to Animal Organization and Physiology

Transport in Animals: the Circulatory System

Reproduction in Animals

Animal Development

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Control

Control of Animal Processes: Neural Integration

Muscles, Skeletons, and Body Movements

Animal Behaviour

Animal Nutrition

Gas Exchange: the Respiratory System

Regulating the Internal Environment

Defences Against Disease

Conservation and Evolutionary Physiology

Filters

In the Hershey and Chase experiment, why was the pellet radioactive after bacteria had been infected with ³²P-labelled viruses and centrifuged?