Question 1

PBDEs are ____.
A) permitted in many European countries but banned in the United States
B) permitted in only one European country and in only 11 states in the United States
C) banned worldwide but are still being used illegally
D) banned in many European countries but permitted in most states in the United States
E) banned in many Europeans countries and all states in the United States

Accepted Answer

PBDEs (polybrominated diphenyl ethers), used as flame retardants, are banned in many European countries due to environmental and health concerns. However, in the United States, regulation varies by state, with most states still allowing their use.

Question 2

New ____ mutations can often be detected by examining the inheritance of the trait in males.
A) mitochondrial
B) imprinting
C) autosomal dominant
D) autosomal recessive
E) X-linked

Accepted Answer

X-linked mutations are inherited in a sex-specific manner, with males having only one X chromosome. Therefore, if a male inherits an X-linked mutation from his mother, he will express the trait. This makes it easier to detect new mutations in males. Autosomal dominant and recessive mutations are inherited in a more complex manner that does not depend on sex. Mitochondrial mutations are inherited from the mother and do not follow typical Mendelian inheritance patterns. Imprinting refers to the differential expression of genes depending on which parent they were inherited from, but it does not necessarily make new mutations easier to detect.

Question 3

What occurs in a missense mutation?
A) All of the amino acids beyond the mutation point are changed.
B) A nucleotide is added to the DNA.
C) A nucleotide is deleted from the DNA.
D) A single amino acid is substituted for another in a protein.
E) The protein is always completely nonfunctional.

Accepted Answer

In a missense mutation, a single nucleotide change results in the substitution of one amino acid in the protein for another. This can potentially affect the function of the protein, but not necessarily render it completely nonfunctional. A and B are incorrect because not all amino acids beyond the mutation point are changed, and a nucleotide is not always added. C is incorrect because a nucleotide is not always deleted. E is incorrect because the severity of the effect on protein function depends on multiple factors and can vary from complete loss of function to no effect.

Question 4

PBDEs have not been linked directly to cancer in test animals.

Accepted Answer

PBDEs have not been directly linked to cancer in test animals. However, they have been shown to have negative effects on the neurological and reproductive systems in animals and humans.

Question 5

Mutations in germ cells are passed on only to other germ cells in members of future generations.

Accepted Answer

Mutations in germ cells can be passed on to offspring, affecting all cells in the body of the offspring, not just their germ cells.

Question 6

Mutation rates of human genes are expressed as the number of ____.
A) nucleotides substitutions per gene
B) frameshift mutations per genome
C) mutated alleles per genome
D) induced mutations per generation
E) mutated alleles per gene in each generation

Accepted Answer

Mutation rates of human genes are typically expressed as the number of mutated alleles per gene in each generation, reflecting how often mutations occur in a given gene across generations.

Question 7

People with cystic fibrosis display a single phenotype for the disorder.

Accepted Answer

Cystic fibrosis is caused by mutations in the CFTR gene which can result in a range of disease severity and symptoms. Therefore, there can be variation in the phenotype observed in individuals with cystic fibrosis.

Question 8

When the number of trinucleotide repeats in a gene is significantly above normal,it can produce a mutant phenotype.

Accepted Answer

This is true. The expansion of trinucleotide repeats in certain genes can cause a range of disorders known as trinucleotide repeat expansion disorders, which include Huntington's disease, fragile X syndrome, and myotonic dystrophy, among others. These disorders exhibit a wide range of symptoms, including neurological dysfunction, developmental delays, and muscle wasting, among others, depending on the gene affected and the length of the trinucleotide repeat expansion.

Question 9

Most often,radiation doses are expressed in terms of damage.

Accepted Answer

Radiation doses are most often expressed in terms of the damage they can cause to living tissue. This damage can be measured in a variety of ways, such as the amount of energy absorbed by the body or the number of mutations in a cell's DNA. The concept of radiation damage is important in understanding the potential health effects of exposure to ionizing radiation.

Question 10

Control systems in the cell can induce cell suicide,or apoptosis,in cells with excessive DNA damage.

Accepted Answer

Control systems in the cell, such as the p53 pathway, can induce apoptosis in cells that have excessive DNA damage as a protective mechanism to prevent the propagation of damaged DNA. This process is important in preventing the development of cancer.

Question 11

When ____ is incorporated into DNA or RNA during synthesis,it will create a(n)____.
A) carbon; base analog
B) oxygen; base analog
C) 5-bromouracil; nucleotide substitution mutation
D) 5-bromouracil; frameshift mutation
E) oxygen; nucleotide substitution mutation

Accepted Answer

5-bromouracil is a base analog that can be incorporated into DNA or RNA during synthesis and causes nucleotide substitution mutations.

Question 12

If a genetic disorder appears in a family with no prior history,and is fully expressed by everyone carrying that allele,it is most likely a(n)____ trait.
A) autosomal dominant
B) autosomal recessive
C) X-linked recessive
D) Y-linked
E) mitochondrial

Accepted Answer

Autosomal dominant traits are expressed in individuals who have just one copy of the allele, which explains why the disorder would be fully expressed by everyone carrying it, even if it appears in a family with no prior history.

Question 13

A mutation of an autosomal recessive trait can remain undetected for generations.

Accepted Answer

Autosomal recessive traits can be masked if the individual possesses at least one dominant allele. Therefore, carriers of the recessive allele can remain unaware of their status and pass on the gene to their children, who may also remain unaffected carriers. This cycle can continue for generations until two carrier individuals have children, who have a 25% chance of inheriting two recessive alleles and expressing the trait.

Question 14

Several lines of research provide strong evidence that ____ to environmental signals influence behavior.
A) epigenetic responses
B) epigenetic feedback
C) base analog reconstruction due
D) base analog reactions
E) base analog responses

Accepted Answer

Epigenetic responses refer to changes in gene expression that are not caused by alterations in the DNA sequence, but rather modifications to the DNA and/or histone proteins that regulate its accessibility. These modifications can be influenced by environmental signals, such as stress or diet, and thus epigenetic responses can strongly influence behavior. The other choices, base analog reconstruction, feedback, and reactions, are not relevant to epigenetics or environmental signals. Base analog responses could potentially be relevant, but this term is not commonly used in this context.

Question 15

Nonsense mutations change termination codons into amino acid codons.

Accepted Answer

Nonsense mutations change amino acid codons into termination codons, causing premature termination of protein synthesis.

Question 16

Mutagenic chemicals that ____ and are incorporated into DNA or RNA during synthesis are called base analogs.
A) resemble nucleotides
B) resemble genes
C) resemble amino acids
D) cause deletion mutations
E) cause frameshift mutations

Accepted Answer

Base analogs are chemicals that resemble nucleotides and can be incorporated into DNA or RNA during synthesis, leading to mutations. They can cause base pair substitutions, as they pair with the wrong base during replication, or induce frameshift mutations by disrupting the reading frame of the genetic code. However, they do not cause deletion mutations, which can result from other types of mutagens.

Question 17

Beckwith-Wiedemann syndrome is a cell growth disorder that causes enlarged organs,high birth weight,and predisposition to cancer.

Accepted Answer

Beckwith-Wiedemann syndrome is a genetic disorder that results in overgrowth of various organs and tissues, including the tongue, liver, spleen, and kidneys. It also causes high birth weight and an increased risk of developing certain cancers, such as Wilms tumor and hepatoblastoma, during childhood.

Question 18

Halogen-containing organic compounds persist in the environment for approximately five years.

Accepted Answer

Halogen-containing organic compounds can persist in the environment for much longer than five years. Some of them, such as polychlorinated biphenyls (PCBs), can persist for decades or even centuries.

Question 19

Genetic imprinting is caused by ____.
A) insertion of a nucleotide into an exon
B) deletion of an amino acid from the mRNA strand
C) a frameshift mutation
D) epigenetic changes to DNA
E) a change in a termination codon

Accepted Answer

Genetic imprinting is caused by epigenetic changes to DNA, specifically modifications to histones and DNA methylation patterns, which can alter gene expression without changing the underlying DNA sequence.

Question 20

What is the largest single source of radiation exposure for the average person in the U.S.?
A) radon
B) medical X-rays
C) cosmic
D) nuclear medicine
E) consumer products

Accepted Answer

Radon gas, which is a naturally occurring radioactive gas that comes from the decay of uranium in the soil, is the largest single source of radiation exposure for the average person in the U.S. It can accumulate in buildings, especially in confined areas like basements and is harmful when inhaled over long periods.

Quiz 11: Genome Alterations - Mutation and Epigenetics

PBDEs are ____.

New ____ mutations can often be detected by examining the inheritance of the trait in males.

What occurs in a missense mutation?

PBDEs have not been linked directly to cancer in test animals.

Mutations in germ cells are passed on only to other germ cells in members of future generations.

Mutation rates of human genes are expressed as the number of ____.

People with cystic fibrosis display a single phenotype for the disorder.

When the number of trinucleotide repeats in a gene is significantly above normal,it can produce a mutant phenotype.

Most often,radiation doses are expressed in terms of damage.

Control systems in the cell can induce cell suicide,or apoptosis,in cells with excessive DNA damage.

When is incorporated into DNA or RNA during synthesis,it will create a(n) .

If a genetic disorder appears in a family with no prior history,and is fully expressed by everyone carrying that allele,it is most likely a(n) ____ trait.

A mutation of an autosomal recessive trait can remain undetected for generations.

Several lines of research provide strong evidence that ____ to environmental signals influence behavior.

Nonsense mutations change termination codons into amino acid codons.

Mutagenic chemicals that ____ and are incorporated into DNA or RNA during synthesis are called base analogs.

Beckwith-Wiedemann syndrome is a cell growth disorder that causes enlarged organs,high birth weight,and predisposition to cancer.

Halogen-containing organic compounds persist in the environment for approximately five years.

Genetic imprinting is caused by ____.

What is the largest single source of radiation exposure for the average person in the U.S.?

Quiz 11: Genome Alterations - Mutation and Epigenetics

PBDEs are ____.

New ____ mutations can often be detected by examining the inheritance of the trait in males.

What occurs in a missense mutation?

PBDEs have not been linked directly to cancer in test animals.

Mutations in germ cells are passed on only to other germ cells in members of future generations.

Mutation rates of human genes are expressed as the number of ____.

People with cystic fibrosis display a single phenotype for the disorder.

When the number of trinucleotide repeats in a gene is significantly above normal,it can produce a mutant phenotype.

Most often,radiation doses are expressed in terms of damage.

Control systems in the cell can induce cell suicide,or apoptosis,in cells with excessive DNA damage.

When ____ is incorporated into DNA or RNA during synthesis,it will create a(n) ____.

If a genetic disorder appears in a family with no prior history,and is fully expressed by everyone carrying that allele,it is most likely a(n) ____ trait.

A mutation of an autosomal recessive trait can remain undetected for generations.

Several lines of research provide strong evidence that ____ to environmental signals influence behavior.

Nonsense mutations change termination codons into amino acid codons.

Mutagenic chemicals that ____ and are incorporated into DNA or RNA during synthesis are called base analogs.

Beckwith-Wiedemann syndrome is a cell growth disorder that causes enlarged organs,high birth weight,and predisposition to cancer.

Halogen-containing organic compounds persist in the environment for approximately five years.

Genetic imprinting is caused by ____.

What is the largest single source of radiation exposure for the average person in the U.S.?

When is incorporated into DNA or RNA during synthesis,it will create a(n) .