Brainscape's Knowledge GenomeTM

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


See full index

Biochem > RNA and Protein Synthesis > Flashcards

RNA and Protein Synthesis Flashcards

1
Q

Where is rRNA made

A

Nucleolus

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

Where is mRNA made

A

Nucleoplasm

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

Where is tRNA made

A

Nucleoplasm

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

What are the mRNA stop codons

A

UGA
UAA
UAG

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

What is the TATA box

A

25 nt upstream, Promoter region for TF binding

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

What is the -10 Pribnow box

A

TATAAT, 10 nt upstream. Promoter region

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

What is the -75 CCAAT box

A

Promoter region

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

What happens to transcription when there’s a promoter mutation

A

Large decrease in level of gene transcription

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

What is the silencer region

A

Site where repressors bind

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

What are the helix-loop-helix and helix-turn-helix

A

Structure in DNA that allows protein to interact with DNA

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

What is the zinc finger motif

A

A structure in DNA that contains a zinc atom and allows protein to bind with DNA

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

What transcribes DNA template into RNA molecule

A

RNA polymerase

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

What is action of RNA polymerase I

A

Makes rRNA in eukaryotes

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

What is action of RNA polymerase II

A

Makes mRNA in eukaryotes

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

What is the action of RNA polymerase III

A

Makes tRNA in eukaryotes

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

What is the smallest RNA

A

tRNA

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

What is the largest RNA

A

mRNA

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

What is the most abundant RNA

A

rRNA (r=rampant)

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

What is the action of alpha amanitin

A

A mushroom toxin that inhibits RNA polymerase II

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

What are the RNA’s in prokaryotes

A

Just 1 RNA polymerase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What antibiotic inhibits prokaryotic RNA polymerase

A

Rifampin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How do prokaryotes terminate transcription

A
  1. Rho factor - RNA dependent ATPase in Ecoli - knocks RNA polymerase off template
  2. Rho-independent - GC rich region, makes strong H bonds that makes a hairpin structure and RNA breaks off
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is hnRNA

A

The initial transcription - heterogenous nuclear RNA

It is RNA that is hot off the presses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How does RNA leave the nucleus

A

It has to be processed - 3 things have to happen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the 3 things you have to do to make mRNA from hnRNA?

A
  1. Cap on 5’ end
  2. Polyadenylation of 3’ end
  3. Splice out introns
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the 5’ cap

A

7-methyl-guanosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What provides 5’ cap

A

SAM: S-adenosyl-methionine

28
Q

What provides the polyadenylation of the 3’ end

A

Poly-A polymerase - adds 200-250 adenines to 3’ end

29
Q

What signal gets poly-A polymerase started

A

AAUAAA

30
Q

What splices the introns before mRNA can leave the nucleus?

A

Spliceosome

31
Q

What amino acid frequently has more coding sequences in the mRNA than are represented in the peptide that is created from it?

A

Methionine (More AUG codons than methionine)

32
Q

How is transcription of the lac operon regulated?

A
  1. CAP - allows RNA pol to bind DNA and start transcription of beta galactosidase gene; won’t bind DNA if glucose present
  2. Lac repressor - prevents RNA pol from binding DNA
33
Q

What is aminoacyl tRNA

A

tRNA that is charged with an amino acid

34
Q

What enzyme charges tRNA with amino acids

A

Aminoacyl tRNA synthetase

35
Q

What is the hydroxyl end of the tRNA

A

3’ end, always ends CCA

36
Q

At what end of tRNA does aminoacyl tRNA synthetase work

A

3’ end

37
Q

Where are ribosomes synthesized?

A

Nucleus, transported to cytoplasm

38
Q

What are the subunits of a eukaryotic ribosome

A

60S and 40S –> 80S

39
Q

What starts initiation in protein synthesis

A

Initiation factors (IFs)

40
Q

What is the role of IFs

A

Help assemble smaller ribosomal subunit with the initiator tRNA (always start with f-met tRNA in prokaryotes)

41
Q

What does IF-2 do in prokaryotic translation

A

First binds 30S, then binds fmet tRNA

42
Q

What allows 50S to attach to 30S?

A

Hydrolyzes GTP on IF, releases energy and allows attachment –> 70S

43
Q

What is the A site

A

Where incoming aminoacyl tRNA binds

44
Q

What is the P site

A

Where polypeptide tRNA binds (chain)

45
Q

What is the E site

A

Where free tRNA located

46
Q

Where does first fMet RNA bind

A

P site

47
Q

What is required to bind an incoming aminoacyl-tRNA to A site

A

Elongation factor EF

48
Q

What part of ribosome has peptidyltransferase activity

A

50S (23S rRNA in prokaryotes)

49
Q

What is elongation factor G

A

Required for translocation in prokaryotes

50
Q

What is required for translocation in eukaryotes

A

EF-2

51
Q

What toxins inhibit EF-2

A 
Diphtheria
Exotoxin A (pseudomonas)
52
Q

What is the release factor

A

Binds stop codon on mRNA and hydrolyzes GTP, releases new polypeptide at T site.

53
Q

Mechanism of aminoglycoside antibiotics

A

Bind 30S subunit early so can’t pair with starter tRNA

54
Q

Mechanism of linezolid

A

Binds 50S subunit so can’t start initiation

55
Q

What antibiotics affect initiation of protein synthesis

A

Aminoglycosides

Linezolid

56
Q

Mechanism of tetracyclines

A

Bind 30S subunit later, prevent aminoacyl tRNA from getting to A site

57
Q

What classes of antibiotics work at 30S subunit

A

Aminoglycosides

Tetracyclines

58
Q

Mechanism of chloramphenicol

A

Inhibits peptidyltransferase part of 50S subunit (23S rRNA)

59
Q

Mechanism of macrolides

A

Bind 50S and inhibit translocation

60
Q

Mechanism of clindamycin

A

Binds 50S and inhibits translocation

61
Q

Antibiotics that affect 50S subunit

A 
Chloramphenicol
Linezolid
Macrolides
Clindamycin
Streptogramins
62
Q

What happens in postranslational modification of trimming

A

N or C terminal are trimmed

63
Q

What cells are notable for making extracellular proteins?

A

Fibroblasts - collagen, fibrilin, elastin
Hepatocytes - albumin, transport proteins, ferritin, coagulation factors
Plasma cells - Ig’s

64
Q

What enzyme matches amino acids to tRNA?

A

Aminoacyl-tRNA synthetase

65
Q

What antibiotics are inhibitors of prokaryotic protein synthesis at 30S subunit?

A

Tetracycline
Aminoglycoside
“Buy AT 30, CCELL at 50”

66
Q

What antibiotics are inhibitors of prokaryotic protein synthesis at 50S subunit?

A 
"Buy at 30, CCELL at 50"
Chloramphenicol
Clindamycin
Erythromycin (macrolides)
Linezolid
Lincomycin

Biochem (10 decks)

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