4A-Enzymes that manipulate DNA

Question 1

What are endonuclease/restriction enzymes

Answer 1

They cut DNA

Question 2

What do ligase do

Answer 2

They glue the DNA back together after it’s cut

Question 3

What do polymerase do

Answer 3

An enzyme that builds a polymer of either DNA or RNA,

Question 4

How do endonuclease know where to cut?

Answer 4

Each are coded to recognise a specific recognition site. When they recognise that sequence, they cut. They cleave the phosphodiester bonds on the recognition site.

Question 5

Sticky ends vs Blunt ends

Answer 5

Blunt ends are cut straight down not along a pair. Sticky ends are jagged Sticky ends are more likely to orientate correctly when paired with a complementary strand of DNA.

Question 6

Two Types of Liagase-

Answer 6

RNA ligase and DNA ligase. They are not gene specific

Question 7

How does ligase and Polymerase work together?

Answer 7

The polymerase runs along the DNA/RNA in sections, leaving gaps in sugar-phosphate bonds. The liagase goes along these replicated strands and reparies and adds sugar-phosphate bonds in these gaps, so that everything is continuous.

Question 8

Polymerase runs from the -

Answer 8

3’ end to the 5’ end