DNA replication - lecture 2 Flashcards Preview

Cell and molecular Biology BB10006 > DNA replication - lecture 2 > Flashcards

Flashcards in DNA replication - lecture 2 Deck (13)
Loading flashcards...
1

What did Arthur Kornberg discover and when?

1959 - discovering the mechanism for biological synthesis of DNA

2

What is the difference between eukaryote and prokaryote replication?

Eukaryote - multiple site of origin, speeds up replication slightly
Prokaryote - one site of replication

3

Does DNA replicate uni or bi-directionally?

DNA synthesis can occur both uni- directionally and bi - directionally.
To replicate bi- directionally , a replication fork must occur .

4

How does the leading strand replicate?

Continuously , in 5' to 3' direction

5

How does the lagging strand replicate?

Discontinuously. Still 5' to 3' .

RNA primate adds an RNA primer to start synthesis.
Polymerase can add Okazaki fragments , after the RNA is added. DNA polymerase 3 lays down new DNA.
Finally DNA ligase joins the fragments together.

6

What does dNTP stand for? what does it do?

deoxynucleotide triphosphate. This is the substrate used to extend the DNA sequence .

7

What type of nucleic acid are the primers?

RNA primers

8

What are the 6 common rules of DNA replication?

- Semi - conservatief
- Starts at 'ori'
- Can be uni or bidirectional
- Semi - discontinuous
- synthesis 5' to 3'
- RNA primers required

9

Topoisomerases

prevents torsion by DNA breaks

10

Singel strand binding proteins

prevent reannealing of single strands

11

Tethering proteins

stabilises DNA polymerase

12

Primase

RNA primer synthesis

13

What are the different polymerase in replication

polymerase 3 - connects the Okazaki fragments
polymerase 1 - turns the RNA primers into DNA