Final - Definitions Ch 15.1

Question 1

Point mutation

Answer 1

A mutation that alters a single base position in a DNA molecule by converting it to a different base or by the insert/deletion of a single base in a DNA molecule

Question 2

Types of point mutations

Answer 2

Base substitutions, base insertions, base deletions

Question 3

Base substitutions

Answer 3

A mutation that exchanges one base pair for another in a DNA sequence
- transitions
- transversions

Question 4

Purines

Answer 4

A and G

Question 5

Pyrimidines

Answer 5

C to T

Question 6

Transition base substitution

Answer 6

Replaces a purine with a purine (A to G or G to A) or a pyrimidine with a pyrimidine (C to T or T to C)
- four possible combinations

Question 7

Transversion base substitution

Answer 7

Replaces a pyrimidine with a purine (C to A, C to G, T to A, or T to G) or vice versa
- eight possible combinations

Question 8

Base insertion

Answer 8

The addition of one base pair

Question 9

Base deletion

Answer 9

the removal of one base pair

Question 10

Indel mutations

Answer 10

Base insertions or deletions

Question 11

Synonymous (silent) mutations

Answer 11

A change to the sequence of a codon that does not change the encoded amino acid

Question 12

Missense (nonsynonymous) mutations

Answer 12

A change to the sequence of a codon to one that codes for a different amino acid

Question 13

Conservative mutation

Answer 13

the replacement of an amino acid by one having similar chemical properties
- missense (nonsynonymous) mutation

Question 14

Nonconservative mutation

Answer 14

the replacement of an amino acid by one having different chemical properties
- missense (nonsynonymous) mutation

Question 15

Nonsense mutations

Answer 15

Change the sequence of a codon that codes for an amino acid into one that stops translation (UAA, UAG, or UGA)
- often produce proteins that are completely inactive

Question 16

Frameshift mutations

Answer 16

single base insertions or deletions