Chapter 13

Question 1

Transition

Answer 1

base substitution in which a purine replaces a purine or a pyrimidine replaces a pyrimidine

Question 2

Transversion

Answer 2

base substitution in which a purine replaces a pyrimidine or a pyrimidine replaces a purine

Question 3

Expanding Nucleotide Repeats

Answer 3

repeated sequence of a set of nucleotides in which the number of copies of the sequence increases

Question 4

Suppressor Mutation

Answer 4

suppresses the effect of an earlier mutation at a different site

Question 5

Intragenic Suppressor Mutation

Answer 5

suppresses the effect of an earlier mutation within the same gene

Question 6

Intergenic Suppressor Mutation

Answer 6

suppresses the effect of an earlier mutation within a different gene

Question 7

Factors that Influence Mutation Rates

Answer 7

size of the gene, nucleotide sequence, spontaneous chemical changes, environment

Question 8

Spontaneous Mutation

Answer 8

mutation that arises from natural changes in DNA structure or from errors in replication

Question 9

Induced Mutation

Answer 9

mutation that results from environmental agents, such as chemicals or radiation

Question 10

Depurination

Answer 10

loss of a purine only

Question 11

Apurinic Site

Answer 11

leads to the incorporation of incorrect nucleotide, typically an adenine

Question 12

Base Analog

Answer 12

chemicals with structures like the four bases of DNA

Question 13

Deamination

Answer 13

the loss of an amino group from a base

Question 14

Intercalating Agent

Answer 14

sandwich themselves between adjacent bases in DNA

Question 15

Ionizing Radiation

Answer 15

dislodges electrons generating free radicals causing double stranded breaks in DNA which causes chromosomal mutations

Question 16

Pyrimidine Dimer

Answer 16

two thymine bases that block replication

Question 17

SOS System

Answer 17

system of proteins and enzymes that allows a cell to replicate its DNA in the presence of distortion in DNA structure

Question 18

Ames Test

Answer 18

test in which special strains of bacteria are used to evaluate the potential of chemicals to cause cancer

Question 19

Deamination

Answer 19

loss of an amino group from a base

Question 20

Incorporated Error

Answer 20

incorporation of a damaged nucleotide or mismatched base pair into a DNA molecule

Question 21

Replicated Error

Answer 21

an incorporate error that is replicated, leading to a permanent mutation