2. DNA Synthesis

Question 1

Direction of New Strand in DNA Synthesis

Answer 1

5’ to 3’

Question 2

Direction of Template Strand in DNA Synthesis

Answer 2

3’ to 5’

Question 3

Pyrophosphate

Answer 3

Two phosphate joined

Question 4

DNA Polymerase Sites

Answer 4

P & E
P: Polymerizing - Correctly synthesized
E: Editing - Leaves if it’s the wrong nucleotides

Question 5

DNA Primase

Answer 5

RNA Synthetase that creates RNA Primer

Question 6

Removal of RNA Primer

Answer 6

RNA Primer is removed by the DNA Polymerase extending the sequence

Question 7

Ligase Activity

Answer 7

Adds a AMP to 5’ end
Release 2P
And joined together as P is released

Question 8

Single strand binding protein (SSBP)

Answer 8

Binds to strand and prevents forming secondary structures

Question 9

Sliding Clamp

Answer 9

Fixes onto DNA Strand so it won’t fall off

Uses ATP

Question 10

Helicase Complex

Answer 10

Helicase
Two DNA Polymerase
DNA Primase
Clamp Loader

Question 11

Helicase

Answer 11

6 parts

Rotates the DNA

Question 12

Topoisomerase I

Answer 12

Cut 1 strand

• Single bond will spin a round
• Saves phosphate by attaching to strand

Question 13

Topoisomerase II

Answer 13

Cuts Both strands

- Uses two ATP

Question 14

DNA Synthesis Starting

Answer 14

• Initiator protein binds to replication origin - AT rich region
• Bent to produce a gap
• Helicase bound to helicase loading protein gets bound onto the DNA
• DNA Primase binds to Helicase

Question 15

3’ overhang

Answer 15

The single stranded part of telomere

- Displaces some H-bonds and stabilizes the end by forming a loop