Genetics 18

Front 1

What is the movement of a transposable element from one location to another called?

Back 1

Transposition

Front 2

A mutation in a gene results in a protein that disrupts a protein-protein interaction. A second mutation in a different gene results in a protein that restores this interaction is called

Back 2

intergenic suppressor mutation.

Front 3

How do cells alter DNA in regions of the genome where transposable elements are common to block production of transposase and inhibit transposition?

Back 3

Methylation

Front 4

Which of the following enzymes makes single-stranded breaks at each end of the transposable element and on either side of the target sequence during transposition?

Back 4

Transposase

Front 5

A mutation which changes a sense codon into a different sense codon, resulting in the incorporation of a different amino acid is called a(n)

Back 5

missense mutation.

Front 6

During transposition, a retrotransposon may be transcribed into RNA to produce double-stranded DNA by which process?

Back 6

Reverse transcription

Front 7

Transposable elements make up at least what percent of human DNA?

Back 7

45%

Front 8

Researchers studied inheritance of Huntington disease within a family for three generations and found that both the age of onset and time to death decreased each generation. This increase in severity of the disease from generation to generation can best be explained by

Back 8

expansion of nucleotide repeats.

Front 9

One of the codons that specifies the amino acid Gly (GGU, GGC, GGA, and GGG) undergoes a single-base substitution to become a nonsense mutation (UAA, UAG and UGA). This mutation is a

Back 9

transversion at the first position of the GGA codon.

Front 10

What is the main organism used in the Ames test?

Back 10

Salmonella typhimurium

Front 11

Which of the following always results from transposition?

Back 11

Movement of a transposable element within the genome or between genomes

Front 12

Diseases caused by expanding nucleotide repeats may become more severe in each generation, which may account for the process known as

Back 12

anticipation.

Front 13

Breaks in double-stranded DNA molecules are most likely to result from exposure to

Back 13

Ionizing radiation.

Front 14

A mutation which changes the amino acid sequence of a protein without altering its function is called a(n)

Back 14

neutral mutation.

Front 15

What is the best characterized mutagenic DNA lesion induced by UV light?

Back 15

Pyrimidine dimer

Front 16

More than half of all spontaneous mutations in Drosophila result from insertion of a(n) _______________ in or near a functional gene.

Back 16

transposable element

Front 17

An example of a disease resulting from a loss-of-function mutation is

Back 17

cystic fibrosis.

Front 18

The error-prone repair system in bacteria that allows for DNA replication across damaged regions is known as

Back 18

SOS repair.

Front 19

Which pair of sequences below might be contained at the ends of an insertion sequence in bacteria?

Back 19

5′-GCGTATAC-3′ and 5′-GTATACGC-3′

Front 20

What is the process called by which fruit flies use small RNA molecules to silence transposase genes and inhibit transposition?

Back 20

RNA interference

Front 21

Mutations due to small insertions and deletions can arise spontaneously during DNA replication due to

Back 21

strand slippage.

Front 22

What is the best characterized mutagenic DNA lesion induced by UV light?

Back 22

Pyrimidine dimer

Front 23

Germ-line mutations

Back 23

are changes in the DNA of gametes.

Front 24

Breaks in double-stranded DNA molecules are most likely to result from exposure to

Back 24

Ionizing radiation

Front 25

What are transposable elements that transpose through an RNA intermediate called?

Back 25

Retrotransposons

Front 26

A mutation that restores the wild-type phenotype through a mutation in a gene other than the one containing the original mutation

Back 26

is an intergenic suppressor mutation.

Front 27

A mutation which changes a sense codon into a different sense codon, resulting in the incorporation of a different amino acid is called a(n)

Back 27

missense mutation.

Front 28

A mutation that can affect the individual in which it occurs but not that individual's offspring is a ___________ mutation.

Back 28

somatic

Front 29

Which of the following is an example of a base analog?

Back 29

5-bromouracil

Front 30

A codon that specifies leucine undergoes a single-base substitution, producing a new codon that specifies methionine. The codons that specify leucine are UUA, UUG, CUU, CUC, CUA, and CUG. The only codon that specifies methionine is AUG. Which of the following correctly describes the mutation?

Back 30

A transversion at the first nucleotide position of a leucine codon