1. 4.1: DNA, and in some cases RNA, is the primary source of heritable information.
N4.02 DNA Replication
Unit 4: Pod 1 DNA

2. The “Central Dogma” Replication Transcription Translation
Unit 4: Pod 1 DNA

3. DNA Replication Allows for heritability of genetic information.
Happens “Semi-conservatively”
Each strand of an old
molecule serves as a
template for the synthesis of a new strand.
Unit 4: Pod 1 DNA

4. The Replisome
All of the enzymes involved in replication function together.
Unit 4: Pod 1 DNA

5. Helicase: Topoisomerase: Opens the helix. Rotates the helix.
Unit 4: Pod 1 DNA

6. DNA Polymerase
Responsible for the addition of new nucleotides to a growing strand.
Can only add nucleotides in the 5’ → 3’ direction.
Makes mistakes.
Unit 4: Pod 1 DNA

7. Directional Synthesis 5’→3’
Polymerase can only make new strands in the 5’ → 3’ direction.
Leading strand: synthesized continuously in 1 piece.
Lagging strand: synthesized discontinuously in multiple fragments, connected by ligase.
Unit 4: Pod 1 DNA