Extra Stuff to know

Question 1

Does ionic strength affect melting temperature?

Answer 1

Yes

Question 2

Is the pribnow box seen in eukaryotes?

Answer 2

No

Question 3

T overhangs on T-tailed vectors are 3’ or 5’?

Answer 3

3’

Question 4

Does DNA polymerase add a single Adenosine residue to blunt ended double stranded DNA on the 3’ or 5’ end?

Answer 4

3’

Question 5

What are the three phases of PCR?

Answer 5

• Denaturation
• Annealing
• Elongation

Question 6

How many bp of DNA wrap around the core histone octamer?

Answer 6

146 bp

Question 7

What type of restriction enzymes can be isoschizomers?

Answer 7

Type II restriction enzymes

Question 8

List five features of active chromatin

Answer 8

• Sensitive to Dnase I digestion
• Core histones are acetylated
• Less compacted ‘beads on a string’
• CpG islands common
• DNA not methylated

Question 9

List five features of inactive chromatin

Answer 9

• Resistant to Dnase I digestion
• Core histones deacetylated
• DNA compacted in 30 nm fibres or higher
• CpG islands rare
• Cytosine methylation

Question 10

What is a σ of transcription? What is it for?

Answer 10

The σ subunit of RNA polymerase in prokaryotes. It recognizes the promoter sequence, this recognition if depended on the type of gene. That is to say that sigma subunits are different for different gene promoters