1. DNA Replication
AP Biology

2. Regents Biology DNA Replication…
THE PROCESS IS _________________
Meaning… _______________________

3. Origins of Replication
Definition: ________________________

4. Where does the energy originate to fuel this reaction?
ANSWER: ________________________

5. Antiparallel Arrangement of DNA
What is meant by antiparallel??
_______________

6. DNA Replication

8. Steps to DNA Replication
DNA unwinds using __________ and opens at _________________________________
_______ ________ is added to a strand by ___________ so DNA polymerase can attach.
At the ________ __________DNA polymerase attaches and adds ________________________
The other strand called ______________ grows also in ______________________ but in ____________________________
A DNA molecule replaces the primer and ___________ glues the segments together

11. The DNA can repair itself!
DNA Polymerase proofreads first.
Mismatch Repair: Sometimes nucleotides are missed and the cell uses special enzymes to fix incorrectly paired bases.
Nucleotide Excision Repair: A nuclease cuts out the damage DNA and the gap is filled with the right nucleotides.
How can DNA be damaged?
What is a “thymine dimer”?

13. What is the purpose of a telemere?
THE PROBLEM: DNA can only be added to 3’ end – how to finish at 5’? Gaps are left and ends become shorter each time
THE SOLUTION: Telemeres do not contain genes but repeated nucleotide sequences (TTAGGG). As a result, as the chromosomes shortens only the repeated units shorten (telemere) rather than the genes!!!

15. What happens if the chromosomes gets too short ?
Telomerase helps restore the ENDS!!