DNA, Mitosis & Cancer

Deoxyribonucleic Acid
1. Molecule that stores the coded information used by cells
  1. Made of two strands of nucleotides which are antiparallel
2. Made up of long chains of units called nucleotides. Nucleotides are made up of:
  1. Phosphate Group
  2. Deoxyribose - pentose sugar
    1. 5 Carbon Sugar
  3. Organic Base which contains nitrogen
    1. Purines (larger bases)
      1. Adenine
      2. Guarnine
    2. Pyrimidine (smaller bases)
      1. Thymine
      2. Cytosine
  4. Nucleotide monomers join together to form polynucleotide strands
    1. Phospahte group of one is linked to the sugar of the next
      1. "Sugar-Phosphate Backbone"
James Watson & Francis Crick
1. Helical structure of the DNA
2. Relative amounts of pyrimidine and purine bases in several organisms
  1. 1:1 ratios for A-T and G-C
    1. Complementary base pairing
      1. AT
        2 Hydrogen Bonds
      2. GC
        3 Hydrogen Bonds
  2. Purines 50%
  3. Pyrimidine 50%
Mitosis
1. Interphase
  1. G1
    1. S
      1. G2
        Short gap before mitosis
      2. DNA replication
    2. Cells prepare for semiconservative replication
2. Prophase
3. Metaphase
4. Anaphase
5. Telophase
6. Cytokinesis
Cancer
1. Mutations in the genes that control cell division, causing rapid, uncontrolled growth and division of cells
  1. Cancer tumour cells do not respond to signals from nerves and hormones
    1. Don't undergo programmed cell death (apoptosis)
2. Treatment

Resource summary

	Created by h.winpenny almost 11 years ago