Mutations and DNA replication/repair Flashcards

1
Q

how does depurination happen

A

bone between base and deozyribose spontaneously hydrolyzes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the most common deamination

A

spontaneous conversion of cytosine to uracil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

how do you get pyrimidine dimers

A

UV light dimnerizes adjacent thymine bases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

somatic muation

A

affects only the cell where the mutation happens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what happens if you have somatic muation early in embryogenesis

A

mosaicism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

germline mutation

A

mutations gets passed to offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

gene mutation

A

variation in nucleotide seque3nces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

genomic mucations

A

surplus o rloss of chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

chromosomal mutaitons

A

rearrangements, deletions, or duplications o fchromosomal regions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

mutations involving chromatin

A

changes in methylation of DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the most common type of mutaiton

A

gene mutation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the 3 mechanisms that cause small insertions and deletions

A

incorrect recomination
strange slippage
intercalating agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what happens iwth incorrect recomination

A

unequal crossover

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

where is incorrect recombination more likely to happen

A

loci that have repetitive DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

where is strand slippage during replication likely to happen

A

areas of repetitive sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

intercalating agents

A

chemical mutagens that fuck up DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what is a source of chromosomal and genome mutation

A

meiosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

prophase I

A

chromosomes condense and become visible

19
Q

synaptonemal complex

A

holds together homologous chromosomes

20
Q

chiasmata

A

sites of crossovers

21
Q

metaphase

A

chromsomes are positioned at the equator

22
Q

anaphase

A

chromsomes are serparted, pulled to opp. poles

23
Q

process of pulling the chromsomes apart and to opposite ends of the cell

A

disjunction

24
Q

nondisjunction

A

incomplete separation of chromosomes in anaphase

25
Q

the frequency of nondisjunction increases with waht

A

maternal age

26
Q

how does gene mapping work

A

use frequency of recombiantion between genes on teh same chromosome as an indicator of their proxiximity

27
Q

3’ –> 5’ exonuclease activity of DNA polymerase delta

A

responsible for bulk of DNA synthsis during replication process

28
Q

what happens if an incorrect nuclteotide is found by the exonuclase

A

it hydrolyzes the new phosphodiester bond adn the polyermase tries again for correct base pairing

29
Q

what is HNPCC caused by

A

defects in mismatch repair system

30
Q

DNA glycosylases

A

recognize specific types of altered base in DNA and catalyze their hydrolytic removal

31
Q

nucleotide excision repair

A

repairs damage caused by agents that result in large changes in structure of DNA

32
Q

waht casues xeroderma pigmentosum

A

mutation that abolism or impair function of nucletoide excision repair

33
Q

symptoms of xeroderma pigmentosum

A

extreme sensitivity of skin to sunlight

34
Q

nonhomoglous end joining

A

you just connect the breaks without adding back what was lost

35
Q

homologous end joinging

A

us the recombination processes to repair broken DNA, no loss of information

36
Q

how is cytarabine different from cytidine

A

contains arabinosine instead of ribose

37
Q

what do you treat with cytarabine

A

acute leukemias

38
Q

how does cytarbine work

A

turns into cytarabine triphosphate inside cells. competes with deoxyribonucleotides for binding to DNA polymerase, blocking DNA replication

39
Q

what do you treat with cyclophosphamide

A

hodgkin’s lymphoma

40
Q

how does cyclophosphamide work

A

acts as alkylating agents, does damage to DNA

41
Q

what is doxorubicin

A

anthracycline antibotic

42
Q

how does doxorubicin work

A

forms complex with DNA and toposimoerase II

43
Q

how does toposiiomerase II work

A

passing 1 double stranged DNA seg throough a double stranged break in another double stranded DNA segment

44
Q

what happens after doxorubicins binds to toposiomerase II

A

double stranded breaks accumulate, lead to apoptosis