MGD9+10

Question 1

What is the shorthand for the substrates of DNA polymerase?

Answer 1

dNTPs

Question 2

What is the shorthand for substrates for RNA polymerase?

Answer 2

NTPs

Question 3

What do transcription factors do?

Answer 3

They recognised certain sequences of DNA and bind to them. They determine the direction of transcription.

Question 4

Where in the sequence does transcription start?

Answer 4

1bp after RNA polymerase binds.

Question 5

What is the promoter for eukaryotes and where is it located?

Answer 5

TATA box

Located at -30

Question 6

What is the promoter for prokaryotes and where is it located?

Answer 6

Pribnow box

Located at -10

Question 7

What is the open reading frame?

Answer 7

The part of the mRNA that is translated.

Question 8

At which end does capping of mRNA occur?

Answer 8

5’ end

Question 9

At which end does polyadenylation of mRNA occur?

Answer 9

3’ end

Question 10

Which RNA polymerase makes rRNA?

Answer 10

RNA polymerase I

Question 11

Which RNA polymerase makes mRNA?

Answer 11

RNA polymerase II

Question 12

Which RNA polymerase makes tRNA?

Answer 12

RNA polymerase III

Question 13

What kind of ribosomes do prokaryotes have and what subunits make up it?

Answer 13

70S

Subunits = 30S and 50S

Question 14

What kind of ribosomes do eukaryotes have and what subunits make it up?

Answer 14

80S ribosomes

Subunits: 40S and 60S

Question 15

In which direction is a protein translated?

Answer 15

N -> C

Question 16

Name the features of the genetic code

Answer 16

triplets, non-overlapping and degenerate

Question 17

What is the start codon?

Answer 17

AUG

Question 18

What are the stop codons?

Answer 18

UAA
UGA
UAG

Question 19

What do you call an activated tRNA?

Answer 19

Amino acyl tRNA

Question 20

What is the aspecific base?

Answer 20

Inosine

Question 21

What is the wobble position?

Answer 21

The 3rd position in the codon

Question 22

What can inosine bond with?

Answer 22

C, U and A

Question 23

What does tRNA synthetase do?

Answer 23

It recognises specific anticodons and adds the correct amino acid to the tRNA to create an amino acyl tRNA.

Question 24

Which subunit of the ribosome binds first?

Answer 24

The smaller subunit

Eg. 40S

Question 25

What is translocation?

Answer 25

The movement of the ribosome along the mRNA during translation.

Question 26

What are the 2 sites in a ribosome called and what do they do?

Answer 26

P site - holds the growing peptide chain

A site - accepts the tRNA to allow a new amino acid to bind

Question 27

Which enzyme is required to from the peptide bonds in translation?

Answer 27

Peptidyl Transferase

Question 28

What is required for translation termination?

Answer 28

water and a stop codon

Question 29

What is a polysome?

Answer 29

A strand of mRNA with many ribosomes attached to it

Question 30

How do bacteria differ in terms of transcription and translation?

Answer 30

They have: simpler promoters, different transcription and translation factors, only one type of RNA polymerase, coupled transcription and translation, no post-transcriptional processing, shorter lived mRNAs and simpler ribosomes.