1. DNA Replication

2. The Model So far: Summarize in the top box, what you know about DNA structure. Why did we start with DNA in our question about how cells reproduce? If you have a sunburn, and your cells are going to divide to form new cells, what will need to be included in the new cell? Which includes the genetic information in DNA, the bases, sugar, or phosphate group?

3. Set up your notes into Cornell Notes: On the edge of your notes: 1)Write this question: Why does DNA have a backbone with really strong bonds, but the bases have weak hydrogen bonds? 2)Next to the question, think of your best answer!

4. DNA Replication DNA replication occurs in the nucleus DNA replication occurs in S phase of the cell cycle before mitosis during interphase (S phase) to make an exact copy of itself for each of the two daughter cells

5. The Process: First Part 1.DNA strands unzip at the H bonds with the help of DNA helicase (an enzyme). 2.Each strand is now a DNA template.

6. 3. Complimentary base pairs attach to the DNA template with the help of DNA polymerase (an enzyme). This reaction is called condensation (dehydration synthesis) *Remember* A T and G C

7. 4. DNA polymerase 1 checks the new DNA strand for errors. 5. If errors are found DNA polymerase 3 corrects them. Errors are important to correct because if you don’t, mutations can occur.

8. 6. Sugars attach to ends of base pairs. 7. Phosphates are inserted between sugars.

9. Final Steps: 8. DNA Ligase glues the two single strands together. 9. This completes DNA Replication.

10. Semi-conservative Replication “parent” “daughter” http://highered.mcgraw-hill.com/sites/0073383198/student_view0/chapter2/animation_quiz_-_dna_replication_fork.html http://www.hhmi.org/biointeractive/dna- replication-basic-detail