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Flashcards in DNA mutations Deck (36):
1

what do mutations start with

a replication error that isn't caught

2

mutations fall in one of three categories

beneficial mutations
neutral mutations
deleterious mutations

3

most mutations are

neutral or slightly deleterious

4

changes one amino acid

missense mutation

5

creates a change in a base that does not change an amino acid

silent mutation

6

changes an amino acid to a stop codon

nonsense mutation

7

when a base is either added to or removed from an mRNA sequence, it will cause a shift in the sequence of frame

insertion or deletion

8

an increase in the number of each type of chromosome

polyploidy

9

the addition or deletion of a chromosome

aneuploidy

10

occur when sections of a chromosome break and rotate before rejoining the chromosome

inversions

11

occurs when a broken section of one chromosome becomes attached o another chromosome

translocation

12

chromosome level mutation can be visualized via

karyotypes

13

strand of DNA is the same as the mRNA sequence

sense strand

14

strand in DNA that is copied by RNA polymerase into RNA

antisense strand

15

all amino acids except two are encoded by more than one codon

redundant

16

one codon never codes for more than one amino acid

unambiguous

17

a few minor exceptions, all codons specify the same amino acids in all organisms

nearly universal

18

the first two bases are usually identical when multiple codons specify the same amino acid

conservative

19

how many bases specify a single amino acid

three

20

what is the start codon

AUG

21

what are the stop codons

UAA
UAG
UGA

22

mechanisms for point mutations typically act through three primary processes

base replacement
base alteration
base damage

23

example of base replacement

analogues

24

example of base alterations

chemical modifications

25

example of base damage

disrupt base-pairing

26

the spontaneous isomerization of a nitrogenous base to/from keto and enol forms or to/from amino and imino forms

tautomeric shift

27

what type of mutations to tautomeric shifts cause

transition mutations

28

where one purine/pyrimidine base pair is replaced with the other purine/pyrimidine base pair

transition mutations

29

removal of amino groups from nitrogenous base

deaminations

30

if cytosine is deaminated what is created

uracil

31

if 5-methylcytosine is deaminated what is created

thymine

32

add ethyl groups to normal base

alkylating groups

33

adds hydroxyl groups to normal base

hydroxylating agents

34

hydrolysis of glycosidic bonds

depurination

35

purine bases are hydrolyzed where

at the ribose glycosidic linkage, leaving the sugar-phosphate backbone in tact

36

most commonly incorporated, leading to a transition mutation

adenine