Title: In Class Activity: DNA Repair
Course: Biochemistry > Section: Week 9 - Unit 4_2: DNA Replication

Purpose: To compare and contrast the synthesis of leading and lagging strand

Over to you:

Watch these videos 1 and 2 then in groups answer the questions below:

Activity:

1. What is DNA repair?
2. Describe the general nucleotide excision repair process.
3. Describe the general base excision repair process.
4. Compare nucleotide excision repair to base excision repair
5. With all these potential sources of DNA damage, why do healthy individuals have a low mutation rate
6. Xeroderma Pigmentosum occurs in 1- 4 per million of the population. This disease is caused by a defect in the early step of nucleotide excision repair Those who suffer from it develop multiple skin disorders and malignancies. Why?
7. DNA can undergo spontaneous damage from the action of water that can result in mutation if not repaired. For example: the deamination of cytosine creates uracil. How would base excision repair remove it? Why would incorporating uracil result in a mutation?