12-3 DNA Replication
Federoff
Eukaryotic DNA Replication
• Step 1 – Helicase unwinds and unzips the DNA
molecule.
• Step 2 – DNA Polymerase adds on
complementary nucleotides in a 5’ to 3’
direction.
• Step 3 – The lagging strand continues to
replicate in fragments instead of continually
like the leading strand.
Okazaki Fragments
• Step 4 – Since the fragments still aren’t joined,
the enzyme ligase, joins the fragments.
• Step 5 – As replication continues, the leading
and lagging strand twist back into their helical
form.
Telomeres
• Are the tips of chromosomes that make it less
likely important genes will be lost with
replication.
Prokaryotic DNA Replication
• Starts at a single
point, and
proceeds in 2
directions until
the entire
chromosome is
copied.
Prokaryotic vs. Eukaryotic
• DNA Replication
• DNAMovie
• Prokaryotic DNA Replication