DNA replication machinery

DNA replication "fork" and enzymes involved in the DNA replicaiton process.
This pic summarizes this class. Click on it for a full size image.

Yesterday we ahd a little change in the class dynamic and it served also as a little experiment. Instead of me lecturing all the time, students were given time to discuss the class topics in bewteen them, and then were asked to present them to their peers.

Several teams of two students explained DNA replication machinery topics, such as templated polymerization, semiconservative replication, replication "fork", Okazaki fragments, etc.

IMPORTANT: Even though we didn't cover all the mateiral up to page 281, these topics should be read and will be included in the next exam on Nov. 4th! These include proofreading mechanisms, and proteins invloved in the replication process.

The pic at the top of this blog entry is a good summary of what we studied in class and what you shoud read to complement what was covered.

Reading for next class: Pages 295-306


Quiz #10 Q&As

1. What is mutation rate?
Rate at which mutations accumulate in a genome

2. How can you measure mutation rate directly?
Sequencing and comparing genomes of an ancestor and some if its descendants

3. How can you measure mutation rate indirectly?
Comparing DNA sequences, especially introns, of closely relates species

4. What is a replication "fork"?
Active region of replication in a parental DNA double helix observed as a 'Y' shaped structure as a result of the separation of DNA strands

5. What is a ‘proofreading’ mechanism in the context of DNA replication?
Chemical mechanisms in which DNA Polymerase "double-checks" that polymerased bases are the right ones (complementary to those in the template strand)


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