Deck 6: Changes in DNA: Mutations and Epigenetics

Question 1

Chemicals found in some pesticides

A) resemble the bases found in DNA.
B) can lead to frameshift mutations.
C) change the structure of DNA bases.
D) cause single-nucleotide substitution mutations.
E) cause mutations by binding to the DNA polymerase.

Answer 1

B

Question 2

Exposure to radiation

A) is easily avoidable.
B) can cause the formation of free radicals.
C) is entirely from exposure to natural background radiation.
D) repairs mistakes made during DNA replication.
E) for the average American is mainly due to dental x-rays.

Answer 2

B

Question 3

For the average American,_____ of radiation dose is due to background radiation.

A) 19%
B) 50%
C) 70%
D) 81%
E) 99%

Answer 3

D

Question 4

The nitrates found in certain food preservatives can cause mutations by

A) incorporating into DNA in place of normal bases.
B) inserting into the DNA helix.
C) modifying the structure of DNA bases.
D) increasing the number of certain trinucleotide repeats.
E) causing nucleotide insertions.

Question 5

The mutation rates for different genes are affected by several factors.Which of the following statements about mutation rates for different genes is FALSE?

A) Gene size affects mutation rates for genes.
B) Nucleotide repeats found in some genes can increase in number with each generation.
C) Genes with many adjacent A/T base pairs often have a high mutation rate.
D) The smaller the gene, the lower the mutation rate.
E) Nucleotide composition does not affect mutation rates of genes.

Question 6

The complete set of genetic information of a human or other organism is called its

A) genome.
B) mutation.
C) chromosome.
D) phenotype.
E) genotype.

Question 7

Free radicals

A) form because of radiation exposure.
B) form due to base analogs.
C) form when atoms have paired electrons.
D) are not reactive.
E) are incorporated into DNA instead of normal bases.

Question 8

Chemicals present in some pesticides

A) resemble the phosphate groups found in DNA.
B) cause base insertion mutations.
C) change the structure of DNA bases.
D) cause single-nucleotide substitution mutations.
E) cause mutations by binding to the DNA polymerase.

Question 9

Free radicals

A) only cause frameshift mutations.
B) form due to base analogs.
C) form when atoms have unpaired electrons.
D) are not reactive.
E) are incorporated into DNA instead of normal bases.

Question 10

Which of the following statements about mutations is true?

A) Mutations in body cells can be passed on to future generations.
B) The only changes due to mutation are in the amino acid sequence of proteins.
C) Mutations in body cells are not known to cause any phenotypic changes.
D) All mutations are single-nucleotide substitutions.
E) Mutations in germ cells can be passed on to future generations.

Question 11

A cell that has accumulated a lot of mutations can have any of the fates below EXCEPT

A) undergoing apoptosis.
B) entering senescence.
C) becoming cancerous.
D) undergoing apoptosis then become cancerous.
E) remaining in a dormant state.

Question 12

Epigenetics involves changes in

A) the sequence of DNA.
B) the expression of genes.
C) the base pairing in the DNA helix.
D) DNA repair systems.
E) DNA replication.

Question 13

Mutations

A) are always easy to detect.
B) always occur in genes.
C) show up at a rate of about 6-7 mutations per child born.
D) are usually only detected when there is a change in phenotype.
E) are always harmful to an individual.

Question 14

Which of the following statements about DNA repair is TRUE?

A) All of the mistakes made in DNA replication are fixed by the proofreading activity of DNA polymerase.
B) There is only one DNA repair system in humans.
C) All mutations are detected and fixed by DNA repair systems.
D) DNA repair systems recognize distortions in the DNA double helix.
E) There is no DNA repair system to deal with damage caused by exposure to ultraviolet light.

Question 15

Mutations are only

A) changes in the nucleotide sequence of DNA.
B) changes in the amino acid sequence of proteins.
C) changes in the nucleotide sequence of RNA.
D) caused by mistakes in DNA replication.
E) caused by environmental agents.

Question 16

Environmental mutagens include certain molecules found in

A) cigarette smoke.
B) vehicle exhaust.
C) some plants.
D) some processed foods.
E) all of these.

Question 17

Base analogs

A) often cause frameshift mutations.
B) lead to single-nucleotide substitution mutations.
C) resemble the sugars found in DNA nucleotides.
D) cause breakage of DNA strands.
E) resemble the phosphate groups found in DNA nucleotides.

Question 18

Researchers have found that when radiation doses are below _____,the major risk is an increase in the risk of cancer.

A) 100,000 rem
B) 360 mrem
C) 1 rem
D) 5000 rem
E) 5000 mrem

Question 19

Types of mutations include all of the following EXCEPT

A) single nucleotide substitutions.
B) insertions.
C) deletions.
D) trinucleotide repeats.
E) methylation of DNA.

Question 20

Frameshift mutations

A) cause a change in the reading frame of mRNA codons.
B) are usually caused by base analogs.
C) usually occur because of radiation exposure.
D) cause a single amino acid change in the polypeptide chain.
E) are usually the result of damage caused by free radicals.

Question 21

Each child is born with 65-70 newly-mutated genes.

Question 22

Methylation of cytosines in CpG sequences

A) is the result of damage from free radicals.
B) does not affect gene expression.
C) is caused by base analogs.
D) leads to the insertion of extra base pairs in DNA.
E) can silence genes.

Question 23

Some mutations can provide an advantage to those who carry them.

Question 24

Mutations only occur in body cells.

Question 25

Mutations are changes in DNA sequence.

Question 26

Epigenetic changes

A) results in unstable phenotypes.
B) requires DNA mutations.
C) are due to distortions in the DNA helix.
D) can be dependent on whether the promoter regions for genes are available for RNA polymerase.
E) are the same for all cells in an individual.

Question 27

Epigenetics is the study of DNA mutations.

Question 28

Beckwith-Wiedemann syndrome (BWS)is caused by

A) abnormal genetic imprinting of two small clusters of genes on chromosome 11.
B) mutations in several genes on chromosome 11.
C) expression of only the maternal copies of all of the genes on chromosome 11.
D) expression of only the paternal copies of all of the genes on chromosome 11.
E) damage to chromosome 11 due to radiation exposure.

Question 29

The main source of radiation exposure for most of the U.S.population is exposure to cosmic radiation.

Question 30

Base insertions usually lead to frameshift mutations.

Question 31

The radiation doses that most people are exposed to are measured in rems.

Question 32

Gene promoters that are tightly wound around a histone complex are easily accessible for RNA polymerase.

Question 33

An average American undergoes a full-body CAT scan.This does not have much of an effect on their annual radiation dose.

Question 34

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
dormant cell

Question 35

Genetic imprinting

A) is due to DNA mutations.
B) affects all genes.
C) assures that both the maternal and paternal copies of each gene are expressed.
D) is due to epigenetic changes.
E) has not been seen in any genetic disorder.

Question 36

Mutations in germ cells are an underlying cause of many types of cancers.

Question 37

Which of the following statements about epigenetics is TRUE?

A) Epigenetic changes occur because of DNA mutations.
B) Epigenetic changes are only due to genetic factors.
C) Epigenetic changes alter the replication of DNA.
D) Epigenetic modifications can be caused by environmental factors..
E) Epigenetic drugs are widely used to treat many genetic disorders.

Question 38

All mutations are harmful.

Question 39

Epigenetic modifications alter the regulation of gene expression.

Question 40

Methylation within the region of a promoter increases expression of that gene.

Question 41

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
cell suicide

Question 42

Cite examples of how nucleotide repeats can cause genetic disorders.How does the number of repeats relate to the severity of the disorder?

Question 43

Explain how each of the following mutagens cause mutations.What are the most common types of mutations caused by each mutagen?
a. base analogs
b. nitrates
c. chemicals in some pesticides

Question 44

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
nucleosomes

Question 45

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
change in DNA sequence

Question 46

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
shift in reading frame

Question 47

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
unit of measure of radiation dose

Question 48

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
CpG sequences

Question 49

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
unpaired electrons

Question 50

Why it is often difficult to diagnose fetal alcohol syndrome (FAS)? What additional measures are usually taken before a diagnosis is made?

Question 51

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
individual's complete genetic information

Question 52

Explain the difference between mutations that occur in body cells compared to mutations that occur in germ cells.

Question 53

What is epigenetics? Describe two epigenetic modifications.What is the effect of epigenetic modifications on the DNA sequence?

Question 54

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
Beckwith-Wiedemann syndrome

Question 55

MATCHING
Match the associated terms.
a.genome
b.millirem
c.apoptosis
d.histones
e.free radical
f.imprinting
g.proofreading
h.mutation
i.methylation
j.frameshift
k.senescence
DNA polymerase

Question 56

How does radiation exposure from dental x-rays compare to our average annual dose from background radiation? What is the average total radiation dose in the United States?