Th2L02 DNA replication

Part of the cell cycle
G1 phase
1. Synthesis of protein components necessary to complete the cell cycle including histones, enzymes for replication, etc.
2. Takes 6-9 hours
S phase:
1. DNA synthesis commences
  1. Overview
    1. (1) DNA unwinds
    2. (2) Daughter strands of DNA produced from parent strand at replication for
    3. Semi conservation replication (each new DNA molecule contains one parent and one daughter strand)
      1. Overall structure of the replication fork
        Replication occurs 3' to 5' along parent strand
        Leading strand
        The new continuous complementary DNA strand synthesised along the template strand in the mandatory 5' to 3' direction.
        Lagging strand
        A discontinuously synthesised DNA strand that elongates by means of Okazaki fragment
        Okazaki fragments
        Small fragments of DNA produced on the lagging strand during DNA replication
        Joined later by DNA ligase to form a complete strand
        Each synthesised in a 5' to 3' direction away from the replication fork.
        New daughter strand is formed 5' to 3'
        One leading strand and one lagging strand
    4. Several enzymes are involved including helicase, DNA polymerase, primase, DNA ligase, etc.
2. Takes 8-9 hours

Resource summary

	Created by Emma Allde over 8 years ago