Gene regulation and protein synthesis

Question 1

central dogma

Answer 1

dna transcribed to rna (nucleotide to nucleotide) and translated to a protein (nucleotide to amino acid)

Question 2

what happens during translation

Answer 2

anticodons of tRNA form base pairs with codons on mRNA

Question 3

how many nucleotides to codons and anticodons consist of

Answer 3

3

Question 4

degenerate

Answer 4

many amino acids have more than one codon

Question 5

unambigious

Answer 5

each codon only codes for one amino acid

Question 6

role of aminoacyl trna synthetases

Answer 6

bind amino acids to their corresponding trna molecules

Question 7

bond between trna and mrna

Answer 7

covalent given from atp

Question 8

how many rrna molecules do ribosomes contain

Answer 8

4

Question 9

how many trna binding sites do ribosomes have

Answer 9

3; exit, peptidyl, aminoacyl

Question 10

what happens to GDP for initiation

Answer 10

is hydrolysed to provide energy

Question 11

steps of initiation

Answer 11

small ribosomal subunit binds to 5 end of mrna
moves along mrna until AUG (start codon) is found
special initiator trna with UAC anticodon pairs

Question 12

steps of elomgation

Answer 12

An elongation factor (EF-1a), brings the next aminoacyl-tRNA to the A site
anticodon base-pairs with codon
GTP is hydrolysed, EF is released from tRNA
A second elongation factor (EFbg) regenerates EF1a to pick up the next aminoacyl-tRNA

Question 13

role of peptidly transferase

Answer 13

catalyses peptide bond formation between amino acids in the P and A sites

Question 14

termination

Answer 14

occurs when a site of ribosome encounters a stop codon

Question 15

where do free ribosomes make proteins destined for

Answer 15

cytosol
nucleus
mitochondria

Question 16

how are proteins from free ribosomes translocated

Answer 16

post translationally

Question 17

bound ribosomes destination

Answer 17

plasma membrane
er
golgi
secretion

Question 18

how are bound ribosome proteins translocated

Answer 18

co translationally

Question 19

post translational modifications

Answer 19

proteolysis
glyosylation
phosphorylation

Question 20

glycosylation

Answer 20

adding sugars

Question 21

proteolysis

Answer 21

breakdwon of proteins into smaller polyppetides

Question 22

function of kinases

Answer 22

catalyse phosphorylation

Question 23

order of cenrtal dogma processes

Answer 23

transcription, splicing, translation, post trans;ational modification

Question 24

what enzyme catalyses dna replicagition

Answer 24

dna polymerase

Question 25

dna ligase

Answer 25

joins okazaki fragment s

Question 26

helicase role

Answer 26

unwinds dna

Question 27

primase

Answer 27

synthesises an rna primer

Question 28

dna polymerase role

Answer 28

catalyses the replication of DNA