M4 Lecture 1

Question 1

What is a gene?

Answer 1

A genetic unit containing information to make a functional product

Question 2

What 4 information must a gene contain?

Answer 2

• Structural = made up of DNA
• Temporal = Must function at right time during life
• Positional = Must switch in its correct targets
• Inducible = Ability to be switched on/off based on different stimulus

Question 3

Can you draw and describe the structure of prokaryotic GENE?

Answer 3

5’ Promoter- transcription start site - leader - Coding region/cistron - spacer DNA - Coding region/cistron - Terminator

Question 4

What is the difference between a cistron and exon?

Answer 4

• Cistron is a segment that forms one peptide
• Exons are made up of many cistrons

Question 5

Can you draw Eukaryotic Class II genes?

Answer 5

Enhancer - Promoter - trasncription start - 5utr- Exon - intron- exon- 3utr

Question 6

Describe the Eukaryotic Class II gene MATURE?

Answer 6

5’ UTR - Exon - 3’ UTR

Question 7

Describe TRANSLATED Eukaryotic Class II gene?

Answer 7

Exons(translated region)

Question 8

Difference between Prokaryotic and Eukaryotic Class II gene?

Answer 8

Eukaryotes contain ENHANCER region

Question 9

What is gene size difference between Prokaryotic and Eukaryotic GENE?

Answer 9

Eukaryotic gene are much larger than the coding required region
Prokaryotic more similar to the size of the required base pairs

Question 10

How does the DNA know in WHICH direction it should start transcription?

Answer 10

• PriBnow Box
  It is a sequence which is exactly 35 and 10 sequences away from transcription start site
  So when RNA polymerase comes in proximity of the start site it RECOGNISE specific PriBnow box sequence
  At -35 is = TTGACA , -10 is = TATAAATG
• On the complementary strand the DNA sequence will be opposite so it will not start transcription there!!

Question 11

What is the Pribnow sequence at -35?

Answer 11

TTGACA