lecture 28

Question 1

what are the TWO types of substitution mutations?

Answer 1

transition and transversion

Question 2

what are exchanged in a transition mutation?

Answer 2

a purine for a purine or a pyrimidine for a pyrimidine

Question 3

what are exchanged in a transversion mutation?

Answer 3

a purine for a pyrimidine

Question 4

do transitions or tranversions occur more commonly? why?

Answer 4

transitions b/c they have similar shapes so they bind more easily

Question 5

what are the THREE types of insertions/deletion mutations?

Answer 5

silent mutations, missense mutations, nonsense mutations

Question 6

what type of mutation involves the changing of one codon to a synonymous codon and causes no change in the amino acid sequence of the protein?

Answer 6

silent mutation

Question 7

what type of mutation is being referred to when “degeneracy of the genetic code” is mentioned?

Answer 7

silent mutation

Question 8

what type of mutation involves the changing of one codon to a different codon and results in a change of the amino acid sequence of the protein?

Answer 8

missense mutation

Question 9

what type of mutation involves the changing of one codon to a STOP codon and results in premature stoppage of translation?

Answer 9

nonsense mutation

Question 10

what type of mutation involves the gain or loss of a nucleotide(s) that results in a change in the reading frame of the codon?

Answer 10

frameshift mutation

Question 11

what type of mutation involves the gain or loss of a nucleotide or trinucleotide set and does NOT change the reading frame of the codon?

Answer 11

in-frame mutation

Question 12

what does amorphic mean?

Answer 12

complete loss of gene function

Question 13

do loss-of-function mutations generally produce phenotypes that are dominant or recessive?

Answer 13

recessive

Question 14

what type of mutation results in a gene that has a gained a new and abnormal function?

Answer 14

gain-of-function mutation

Question 15

what does neomorphic mean?

Answer 15

a new or different function from normal

Question 16

do gain-of-function mutations generally produce phenotypes that are dominant or recessive?

Answer 16

dominant

Question 17

what are somatic cells?

Answer 17

non sex cells

Question 18

what are germ cells?

Answer 18

sex cells (gametes)

Question 19

in what type of cells does a mutation cause a more severe manifestation and passes it does to future generations?

Answer 19

germ cells/gametes/sex cells

Question 20

what type of mutation has no external regulator or artificial factor causing it?

Answer 20

spontaneous mutation

Question 21

what type of mutation is a replication error?

Answer 21

spontaneous mutation

Question 22

what allows non-complimentary bases to pair in a process known as “wobble”?

Answer 22

flexibility of DNA double helix

Question 23

what type of replication error involves denaturation and displacement of DNA strands that results in a mispairing of bases?

Answer 23

slipped strand mispairing

Question 24

what type of mutation is caused by normal chemical interactions that take place within the cell?

Answer 24

chemical changes

Question 25

what type of chemical reaction involves a beta N-glycosidic bond being cleaved by hydrolysis that results in the release of an adenine or guanine from the DNA strand?

Answer 25

depurination

Question 26

what type of chemical reaction involves the hyrdrolytic removal of an amine group from a nucleotide releasing ammonia and converting the nucleotide to another molecule?

Answer 26

deamination

Question 27

the conversion of cytosine to uracil, releasing ammonia, is an example of what?

Answer 27

deamination

Question 28

what is the most common single nucleotide mutation in DNA?

Answer 28

5-methycytosine to thymine deamination process