Structure of DNA Notes

• The 2 types of bases for DNA are Pyrimidine and Purines
• What are the two types of bases for DNA?

  Purines and Pyrimidines
• Purines: Guanine and Adenine
• Pyrimidine: Cytosine and Thymine
• Adenine pairs with Thymine
• Cytosine pairs with Guanine
• Complimentary pairs - the bases that match with eachother
• There are 2 hydrogen bonds for Adenine and Thymine
• There are 3 Hydrogen bonds for Guanine and Cytosine
• hydrogen bonds are weak, covalent bonds are stronger
• Hydrogen Bonds connect base pairs
• Antiparallel direction - DNA strands run in opposite directions
• Sugar-Phosphate Backbones are held by covalent bonds
• Purines pair with Pyrimidines
• DNA has a double helix shape
• 5:3 proves antiparallel direction