DNA replication

Question 1

What is the difference between DNA replication and transcription?

Answer 1

DNA replication makes 2 full DNA chains out of 1, while in transcription mRNA is made to use as a template for protein synthesis

Question 2

What enzyme unwinds DNA in initiation and how does it work?

Answer 2

DNA Helicase - starts at replication origins and unzips the DNA forming a Y shape

Question 3

In which direction does the leading stand go?

Answer 3

5’ to 3’

Question 4

What is the name of the fragments that the lagging strand is made from? And what is name od the enzyme that sticks them together

Answer 4

Okazaki fragments, DNA ligase

Question 5

What enzyme synthesises the start if the RNA stand?

Answer 5

DNA primase

Question 6

What are the 2 types and roles of DNA polymerase?

Answer 6

Polymerase III - elongates from DNA primase

Polymerase I - replaces RNA primer made by primase with DNA

Question 7

What are the 3 proteins associated with DNA mismatch repair?

Answer 7

Mut S, Mut L and Mut H

S and L bind to the mutation at its site, guiding H to the site. Once all 3 have bound DNA polymerase re-synthesises DNA