Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Medical Genomics > Med Genomics > Flashcards

Med Genomics Flashcards

You may prefer our related Brainscape-certified flashcards:
USMLE® Step 1 flashcards
1
Q

the phosphate group is responsible for the strong ___ charge of the nucleic acid

A

negative

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

parental double helix divides into two double helix DNA with one parental strand in each of the two double helices

A

semiconservative replication of DNA

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

describe eukaryotic and prokaryotic DNA

A

eukaryotic - very long with multiple origins of replication

prokaryotic - circular with one origin of replication

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

bind to specific nucleotide sequences at ORIGINS of replication (area usually rich with A&TS) - ATP required - causes double stranded DNA to melt causing strands to separate to form 2 single stranded DNA

A

DnaA protein

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

also called helix destabilizing proteins; protein that protects DNA from nucleases that cleave the single stranded DNA

A

Single stranded DNA binding proteins (SSB)

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

binds to single stranded DNA near replication fork and move further into double stranded regions of DNA forcing the strands apart/unwinding the double helix - ATP required

A

DNA helicases

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

replication of double stranded DNA is ____

A

bidirectional

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

what results from DNA strand seperation

A

positive supercoiling

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

what is responsible for removing supercoils in the helix

A

DNA topiosomerases

actions inlcude - nuclease (cut) and ligase (reassemble)

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

direction of DNA replication

A

reading - 3 –> 5
create - 5 –> 3

reading when your 3 is ok, but creating a fort at 5 sounds more fun

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

strand that is being copied in the direction of the advancing replication fork is called

A

leading strand - synthesized continuously

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

strand that is being coped in the direction away from the replication fork is called

A

lagging strand - synthesized discontinuously - ozaki fragments

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

what are short stretches of discontinuous DNA called

A

ozaki fragments

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

DNA polymerase 3 has ______ activity (building)

A

5 –> 3 polymerase activity (builds) - antiparallel to parental strand

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

DNA polymerase 3 has ______ activity (prooofreading)

A

3 –> 5 exonuclease activity (proofreads)

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

what activity is used to exicse mismatched nucelotides during proofreading of newly synthesized DNA

A

3 –> 5 exonuclease

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

what is a short double stranded region consisting of RNA base paired to the DNA template

A

RNA primer

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

what synthesizes the short stretches of RNA (ten nucelotides long) and complementary and antiparallel to DNA template

A

primase (specific RNA polymerase)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

DNA polyermase 3 will recognize the ____ and begin to synthesize DNA

A

RNA primer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

DNA 3 continues to synthesize DNA on lagging strand until it is blocked by _____; then the answer will be excised and the gap will be filled by ____

A

RNA primer

DNA polymerase 1

21
Q

As DNA polymerase replaces RNA with DNA in the ___ direction, synthesizes DNA in the ___ direction and proofreading the new strand in ____ direction

A

replace RNA with DNA - 5 –> 3 exonuclease activity
sythesizing - 5 –> 3 polymerase activity
proofreading - 3 –> 5 exonuclease activity

22
Q

ozaki fragments are joined by what enzyme and bond

A

DNA ligase - formation of phosphodiester bond

23
Q

a multisubunit enzyme (one subunit has primase acitvity) which INITIATES strand synthesis on the leading strand and beginning of each ozaki fragment on the lagging strand

A

pol alpha

24
Q

a protein recruited to COMPLETE DNA synthesis on leading strand and elongate each ozaki fragment

A

pol delta

25
Q

if didnt work properly it would cause cancer - mitotic clock

A

telomerase

26
Q

removal of abnormal bases involves what

A

glycosylase

27
Q

a thymine without the methyl group is what

A

uracil

28
Q

inherited syndromes with defects in DNA repair

  • colon cancer
  • cellular UV sensitivity/ skin cancer
A
  • colon cancer - mismatch repair

- UV sensitivity - nucleotide excision repair *********

29
Q

where does translation occur

A

cytosol!!

not nucelus

30
Q

functions of RNA 1,2,3

creates precursor to what??

A

1 - large ribosomal RNA
2 - messenger RNA
3 - transfer RNA, small ribosomal RNA

31
Q

mRNA and tRNA are synthesized where?

ribosomal RNA?

A

mRNA and tRNA - nucleoplasm

rRNA - nucleolus

32
Q

what acts over long distances to reduce the level of gene expression

A

silencers and enhancers

33
Q

tRNA contains what

A

ACC

bases added

34
Q

explain introns and extrons

A

introns - intervening sequence

exons - expressive info

35
Q

what forms a splicesome

A

primary transcript combines with snRNPs fold into complex

36
Q

what disease cause antibodies against snRNPS

A

systemic lupus erythrematosus

37
Q

what forms the mature mRNA

A

exons

38
Q

characteristics of genetic code

A

specificity
universality
degeneracy
non overlapping and commaless

39
Q

when genetic code is redundant where some amino acids have more than one triplet coding for it (ex. arginine)

A

degeneracy

40
Q

Components required for translation

A

amino acids
atp and gtp
protein factors

41
Q

what is required in the last two steps of initiation and translation

A

GTP

42
Q

translocation - after the petide bond is formed, the ribosome advances three nucelotides toward the 3 end of the ____

A

mRNA

43
Q

initiation codon aug is recognized by special initiator tRNA that enters the ___

A

p site

44
Q

formation of peptide bonds is catalyzed by what

A

peptidyltransferase - found in rRNA 28S found in 60s ribosomal subunit - ribozyme because rRNA catalyzes the reaction

45
Q

termination occurs when the three termination codon moves into the __

A

a site

46
Q

termination codon is recognized by a _____ that activates and release new peptide

A

release factor

47
Q

posttranslational modification of polypeptide chains

  • phosphorylation
  • glycosylation
  • hydroxylation
  • carboxylation
A

phosphorylation - serine and tyrosine
glycosylation - o and n linked
hydroxylation - proline, collagen, vit C
caboxylation - glutamate and vit K

48
Q

protein degradation

A

protein tagged for degradation with molecule of ubiquitin

ubiquinated proteins are recognized by cytosolic proteasome which unfolds the protein and transports the protein to proteolytic core

49
Q

unlike DNA polymerase, RNA polymerase …

A

does not require a primer and has no known endonucleases or exonucleases, therefore cant repair mismatch

Medical Genomics (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions