Transcription

Question 1

What is heterochromatin?

Answer 1

Coiled up DNA (solenoid) that contains genes which are not expressed

Question 2

What is euchromatin?

Answer 2

DNA in a ‘beads on a string’ formation containing genes that are expressed.

Question 3

What is needed for initiation of transcription?

Answer 3

Transcription initiation factors

RNA polymerase

Question 4

In what direction does the mRNA chain elongate?

Answer 4

5’ to 3’

Question 5

What is the DNA code that normally acts as the promotor region for transcription?

Answer 5

TATA

Question 6

Name 2 protective processes mRNA goes through

Answer 6

Capping- at 5’ end

Polyadenylation- at 3’ end

Question 7

What happens to pre-mRNA to become mature mRNA?

Answer 7

Splicing. Introns are removed.

Question 8

What is capping?

Answer 8

A 5’ to 5’ linkage which provides protection to the mRNA chain

Question 9

What is polyadenylation?

Answer 9

The finished RNA chain has a very long adenine chain added to the 3’ end to protect the mRNA.

Question 10

What is an intron?

Answer 10

A non-coding section of DNA

Question 11

Where does transcription occur?

Answer 11

Nucleus