Lecture Exercises

Overview of the Process of DNA Replication

New nucleotides can only be added to a three-prime end.
Because the strands are anti-parallel, the three-prime end

• is facing the replication fork on the leading strand
• is facing away from the replication fork on the lagging strand

Step 2: Build Complementary DNA

How do we denature DNA strands in the lab?
Temperature

The DNA polymerase we use in the lab is called taq polymerase.

If we use regular polymerase, the polymerase is going to degrade as the temperature goes up.
We find a polymerase that can withstand high temperatures from a bacteria called Taq Thermus Aquaticus

CRISPER/Cas9
Major revolution in biotechnology Allows you to cut specific pieces of DNA Where does CRISPER/Cas9 come from?
Bacteria have a self defense system. We borrow from the bacteria in the same way we borrow the polymerase from the Taq Thermus Aquaticus.
We discover these tools when we study biology diversity.

Step 2: Build Complementary DNA - The Replication Forks ***

INFO

Timestamp March 7, 2024 10:15 AM

I might give you a replicate bubble like thise. I might only give you the replication strand.
Maybe I'm only showing you a strand.
I will ask you, is that going to be leading strand or a lagging strand.

Identify where the prime end is, understand that it's antiparallel, and identify which it is.

Example question:

5'                 3'
____________________
 3'------5'
____________________
3'                 5'

Answer: Leading strand

Example question:

3'                 5'
____________________
   5'------3'
____________________
5'                 3'

Answer: Lagging strand