Module 2 Section 1

Question 1

Stages of Eukaryotic Cell cycle

Answer 1

1. G0/G1 phase
   - cells not actively dividing, first growth phase
2. S phase (synthesis)
   - cell replicates entire genome
3. G2 phase
   - last chance for cells to grow before division
4. M phase
   - where cell division occurs
   - cell divides into 2 identical daughter cells

Question 2

Kornberg replication of polymerase steps

Answer 2

1. break bacteria by sonification
   2-5. remove DNA/RNA from mixture
2. use salt to precipitate some proteins, leaves others in solution
3. use ion-exchange chromatography to give purified product
   -at each stage, protein content measured with SDS-PAGE
   -measured the ability of protein of interest to perform its function

Question 3

Results of Kornberg experiment

Answer 3

• deduced requirements of a polymerase rxn by removing critical components of replication rxn
• observed there was near complete loss of enzyme activity

Question 4

Requirements of polymerization reaction

Answer 4

1. all 4 dNTPs present in cell
2. intact DNA template
3. Mg++ cofactor for the polymerase