Proposed Models of DNA Replication
The semi-conservative model supported by Watson and Crick is
The three phases in DNA Replication
1. Initiation: The double helix unwinds and exposes the bases. Proteins bind to the orgin of replication
2. Elongation: Two new strands of DNA are created by using the parent DNA as a template. The leading and lagging strands are "photocopies" of the DNA. Primers help add RNA sequences, later replaced by DNA sequences.
3. Termination: Primers are removed and the DNA sequence is sealed.
Enzymes that take part in replicaiton:
- I - Helicase: Unwinds the double helix DNA, providing single-strand template
- I - Gyrase: Relieves strain while DNA is unwound by helicase
- E - SSBP or Single Stranded Binding Protein: keeps strand from snapping back into helix shape
- E - Primase: Helps create RNA primer
- E - Primer: Attaches to template, DNA polymerase able to add on
- E - DNA Polymerase: "proofreads" corrects nucleotides
- E - Ligase: "Cements" fragments into strand
tbc...
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