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Flashcards in translation Deck (77):
1

how many types of bases in nucleic acid

4

2

how many types of bases in nucleic acid

4

3

how many amino acids

20

4

how many possible codes

64

5

DNA is...

universal, non-overlapping and degenerate

6

degerate

same amino acid coded for by a number of codes

7

translation directn

5' to 3'

8

three roles of RNA in translation

1) mRNA--> transporting DNA info from nucleus 2) ribosomal RNA- makes up the ribosome where translation occurs 3)tRNA--> deciphers the codons on the mRNA

9

where does translation occur

in the nucleus' ribosome

10

ribozyme

an RNA molecule capable of acting as an enzyme.

11

tRNA is responsible for the catalysis of..

peptide bond formation

12

tRNA

-clover shaped molecule with is produced in the nucleus and resides in the cytoplasm -it has anticodons and an acceptor stem which attaches to specific amino acids

13

where is tRNA produced

the nucleus

14

what couples tRNA with specific amino acids

specific enzymes- diff for all tRNA

15

the anti-codons pair with..

codons on the mRNA, delivering its amino cid in the correct sequence

16

how is the amino acid sequence perfected

due to the compatibility of anti-codons on tRNA and codons on mRNA

17

a ribosome is..

a large complex of 4 RNAs and more than 82 proteins

18

ribosomal unit structure

on the ribosomal subunit there are 3 sites 1: A site- aminoacyl-tRNA site 2: P site= peptidyl- tRNA site 3: E site- exit site Made up of a large ribsookmoal sub unit and small subunit

19

the ribosome is made up of...

a large ribosomal subunit- 49 proteins and 3 RNA a small ribosome subunit-33 proteins and 1 RNA and various sites

20

the ribosome is made up of...

a large ribosomal subunit a small ribosome subunit and various sites

21

how many amino acids

20

22

how many possible codes

64

23

DNA is...

universal, non-overlapping and degenerate

24

degerate

same amino acid coded for by a number of codes

25

translation directn

5' to 3'

26

three roles of RNA in translation

1) mRNA--> transporting DNA info from nucleus 2) ribosomal RNA- makes up the ribosome where translation occurs 3)tRNA--> deciphers the codons on the mRNA

27

where does translation occur

in the nucleus' ribosome

28

translation ends with

mRNA and ribosomal subunits dissembling an the release of a newly synthesised protein

29

tRNA is responsible for the catalysis of..

peptide bond formation

30

tRNA

-clover shaped molecule with is produced in the nucleus and resides in the cytoplasm -it has anticodons and an acceptor stem which attaches to specific amino acids

31

where is tRNA produced

the nucleus

32

what couples tRNA with specific amino acids

specific enzymes- diff for all tRNA

33

the anti-codons pair with..

codons on the mRNA, delivering its amino cid in the correct sequence

34

how is the amino acid sequence perfected

due to the compatibility of anti-codons on tRNA and codons on mRNA

35

rRNA

RNA component of the the ribosomes

36

a ribosome is..

a large complex of four RNAs and more than 80 proteins

37

tRNA in the E site will not have

an amino acid- it is released after a peptide bond is formed between tRNA molecules in the P and A site

38

the ribosome is made up of...

a large ribosomal subunit a small ribosome subunit and various sites

39

there are no tRNA that match the..

stop codon sequence

40

3 steps of translation

1) initiation 2)elongation 3)termination

41

1) initiation

- initiates at the first (5') AUG codon - when the small unit of ribosome is in place, it will delineate (indicate the exact position) where the two sites of translation will be -AUG codon is bound to the initiator tRNA- therefore the first amino acid in the polypeptide chain will always be METHIONINE -this allows the large subunit to bind and the ribosome to assemble -p site is filled with initiator tRNa but the A-site is empty

42

first codon of translation is always

AUG

43

AUG codes for

methionine

44

experiment that crick and brenner did to crack the eugenic code

used bacteriophage T4(virus' which infect and replicates inside bacteria) which infects E-coli -by generating mutants in the RII gene of bacteriophage T4 using proflavin -causing a 'rapid lysis' phenotype of larger plaques

45

proflavin

a planar molecule, intercalates between base paris in DNA -causes 'frameshift' mutations -insertion of an extra base of deletion of a base

46

stop codons ar bound by

termination factors

47

translation ends with

mRNA and ribosomal subunits dissembling an the release of a newly synthesised protein

48

amino acids on the tRNA are selected by..

their codons on the mRNA

49

initiator amino acid carried on the initiator tRNA

methionine

50

what scans for the start codon

the initiator tRNA and the bottom part of the ribosomal subunit- the top part of the ribosomal subunit only joins after AUG has been found

51

where is the initiator tRNA's site on the ribosomal rna

p-site

52

e-site

exist site for tRNA after it is done delivering the amino acid

53

new (non initiator tRNA) enter the

A site

54

what happens to adjacent amino acids in the ribosome

a peptide bond is formed

55

when peptide bond is formed

the amino cid in the p site will release its amino cid and move into the E site- the tRNA in the A site will move into the P site and now the A site is empty for a new tRNA with an amino acid on it to enter

56

there are no tRNA that match the..

stop codon sequence

57

who tried to crack the genetic code

crick and brenner

58

how many bases correspond to one amino acid

3

59

cricks hypothesis with triple mutations which proved that the genetic code was triplet (+++)

THE XBI GYR EDZ FOX ATE THE EGG makes sense

60

evidence for the code not being overlapping -- simple

because single base mutations only ever affect one amino acid

61

experiment that crick and brenner did to crack the eugenic code

used bacteriophage T4(virus' which infect and relicate inside bacteria) which infects E-coli -by generating mutants in the RII gene using proflavin -cuasing a 'rapid lysis' phenotype of larger plaques

62

proflavin

a planar molecule, intercalates between base paris in DNA -causes 'frameshift' mutations -insertion of an extra base of deletion of a base

63

the proflavin and (+) and (-)

the proflavin caused base inseriont (+) and base deletions (-) --> these causes bacteriophages which were different to their wild types

64

wild type

a strain, gene, or characteristic which prevails among individuals in natural conditions, as distinct from an atypical mutant type.

65

double mutants- (+-)

wild type

66

double mutants - (++)

RII mutation

67

double mutants (--)

RII mutation

68

double frameshift mutants of the same type will still have..

mutant phenotypes

69

triple mutants (+++)

wild type

70

triple mutants (---)

wild type

71

triple mutants (+-+)

RII

72

wild type message- CRICKS HYPOTHESIS

THE BIG RED FOX ATE THE GG

73

cricks hypothesis with single (+)

causes a frame shift so the message now reads THE XBI GRE DFO XAT ETH EEG G -this makes no sense

74

cricks hypothesis with double mutation (++)

THE XBI EDF OXA TET HEE GG -makes no sense

75

cricks hypothesis with double WT mutation (+-)

THE XBI GRD FOX ATE THE EGG -psuedo wild type

76

some tRNAs can tolerate a mismatch at the third codon position- this is called a

wobble

77

three codons that do not code for an amino acid

stop codon