Chapter 8: DNA and RNA

1
Chapter 8DNA and RNA

• Section 8-2B
• DNA Replication

2
DNA Replication

• If the two strands separate, the sequence of
  bases on each strand can be used as a template to
  form an exact duplicate
• Replication occurs during the S phase of the cell
  cycle and is semiconservative
• Carefully controlled by enzymes
• Strands are separates, new strands created by DNA
  polymerase

3
DNA and Chromosomes

• In eukaryotes, DNA is contained in chromosomes in
  the nucleus
• Chromosomes are DNA and proteins (more protein
  than DNA)
• Chromatin is the material that makes up
  chromosomes

4
DNA and Chromosomes

• Histones are proteins that bind directly to DNA
• Histone DNA wrapped around it nucleosome
• Nucleosomes help package DNA into chromosomes
  (also aid in transcription)
• The DNA in a single chromosome may by 10,000X
  longer than the chromosome itself

5
Animations

• http//highered.mcgraw-hill.com/sites/0072437316/s
  tudent_view0/chapter14/animations.html
• http//207.207.4.198/pub/flash/24/menu.swf
• http//www.pbs.org/wgbh/nova/genome/dna.html