11.05.2013 Molecular Biology 4 Flashcards Preview

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Flashcards in 11.05.2013 Molecular Biology 4 Deck (44):
1

Accurate mechanism for replication
-repair of accidental lesion
--is required for genetic (instability/stability)

stability

2

(transition/transversions)substitution of a pyrimidine with a purine or vice versa.

tranversion

3

(transition/transversions)substitution of a pyrimidine with another pyrimidine or a purine with another purine.

transition

4

First level of repair during replication is ?

3' to 5' exonuclease activty of DNA polymerase

5

T/F Distortion in the DNA helix is recognized and repaired by strand-directed mismatch repair

T

6

Single strand breaks or nicks provide the repair signal.
-mechansims for recognizing mismatch in (e.coli/mammalian cells)

mammalian cells

7

Both strands are methylated (dam methylase) at A in the sequence GATC.
There is a lag in the methylation of GATC sequence in the newly synthesized strand
(e.coli/mammalian cells)

e.coli

8

(MutS/MutL) recognizes mismatched bases

Mut S

9

(MutS/MutL)scans the DNA
for a nick to determine
the newly replicated
DNA.

MutL

10

T/F Colon cancer phenotype has FAP stands for familial adenomatous polyposis and HNPCC stands for hereditary non-polyposis

T

11

(transversions/frameshift) due to addition/deletion of bases

frameshift

12

Cellular metabolic activity
Heat
Extreme pH
Radiations
Substances in environment
--- can all case what?

structural alteration in DNA bases

13

(spontaneous changed/UV damage) sepurination, deamination

spontaneous changed

14

(spontaneous changed/UV damage) pyrimidine dimers

UV damage

15

(Depurination/deamination) converst C to U

damination

16

(Depurination/deamination) removes a purine from the nucleotide

depurination

17

which one of the DNA bases would not undergo deamination?
(guanin/cytosine/thymine)

thymine has no amino group

18

T/F mehtylated cytosine is commonly found in DNA

T

19

Uv induces pyrimidne (A or G/ Cor T) dimers

C or T

20

(deamination/depurination) changes the base

deamination

21

(deamination/depurination) leads to deletion

depurination

22

(Base excision repair/Nucleotide excision repair)Specific base is removed and repaired

Base excision repair

23

(Base excision repair/Nucleotide excision repair)A stretch of DNA strand is removed and new strand with correct base is synthesized

Nucleotide excision repair

24

(T/U) is an unusual base for DNA

U

25

(RAD3/RAD6/RAD52)excision repair

RAD 3

26

(RAD3/RAD6/RAD52) recombination-mediated repair

rad6

27

(RAD3/RAD6/RAD52) post replication repair

rad 52

28

yeast is best model system characterized for (prokaryote/eukaryotic) repari

eukaryotic

29

T/F active genese are preferentially repaired

T

30

(RAD3/RAd6) a helicase is required for repair is componenet of transcription factore associated with (DNA/RNA) polymerase

Rad3, RNA

31

recombination , ionizing radiation
-double stand breaks are(repaired/occur)

occur

32

Homologous end-joining (HEJ)
Non-homologous end-joining (NHEJ)
double strands breaks are (repaired/occur)

repaired

33

(nonhomologous/homologous) end-joining results in loss of original sequence

non-homologous

34

(nonhomologous/homologous) repair of double stranded breaks has no loss of sequences

homologous

35

T/F BRCA1 and BRCA2 predispose women to breast and ovarian cancer

T

36

(BRCA1/BRCA2) 1863 amino acids

BRCA1

37

(BRCA1/BRCA2) 3418 amino acids

BRCA2

38

(BRCA1/BRCA2)also involved in transcriptional regulation of genes activated in response to DNA damage.

BRCA1

39

(BRCA1/BRCA2)Initial studies indicated involvement of BRCA1 in repairing DNA damage.

BRCA1

40

BRCA1 and BRCA2 interact with other proteins that activate repair of double strand breaks and initiate (homologous/nonhomologous) recombination.

homologous

41

Werner syndrome is autosomal recessive what type of manifest in the eye does it have?

cataracts

42

Autosomal recessive:
stunted growth
sunlight sensitivity
chromosome breakage
immunologic deficiency
infertility
increased risk for neoplasia
--describes (bloom syndrome/werner syndrome)

bloom syndrome

43

Autosomal recessive
cataracts
changing of skin conditions
atypical short stature
premature graying or thinning of the hair.
Patients also often develop hypogonadism, osteoporosis, diabetes mellitus, atherosclerosis and cancers (sarcomas)
--describes (bloom syndrome/werner syndrome)

werner syndrome

44

both werner syndrome and bloom syndrome mutations in the helicase of Rec Q family

T