DNA Notes
Biology: Dr. Hensley / Mrs. Ingram
Feb. 2016
Chromosomes and DNA Replication
 DNA duplication takes place in the “S” phase of the cell cycle
 DNA is found in the nucleus of a eukaryotic cell; linear DNA
 DNA is found in the cytoplasm of a prokaryotic cell; single, circular DNA
Eukaryotes have 1000X more DNA than Prokaryotes!!!!
DNA Structure:
1.
2.
3.
4.
5.
Double Helix
Wraps around proteins called Histones
Nucleosome – DNA wrapped around Histones
Coils
Super Coils
6. Chromosome
DNA Polymerase: “ase”= enzyme “polymer” = build big
Makes a new DNA strand identical to the old one
DNA Replication Fork – where DNA
opens up
Model of what
Goes on other side
Template or Original
Strands (parent strands)
provide a guide for DNA
polymerase to making
new strands of DNA
Things to Remember About DNA Replication