DNA

• DNA


  Deoxyribonucleic acid, codes for amino acid sequences which are the primary structure in proteins
• DNA


  • Every single cell has its own copy except for red blood cells
  • Needs to be protected because it is the code for all the proteins in a cell
• DNA nucleotide


  Contains a phosphate group, a pentose sugar (deoxyribose), and a nitrogen containing base (guanine, cytosine, adenine, thymine)
• DNA polymer formation


  1. Condensation reaction between phosphate group and deoxyribose

  2. Forms phosphodiester bond
• Phosphodiester bond


  Strong covalent bond that holds the DNA nucleotides together
• Sugar phosphate backbone


  Strong backbone of DNA molecule
• DNA structure


  • Double stranded, forms a double helix
• Complementary base pairing


  Cytosine pairs with guanine, adenine pairs with thymine
• Complementary base pairing


  Allows for DNA replication to create identical copies
• DNA double helix


  • Strong covalent bonds on the outside, weaker hydrogen bonds in the middle
  • Can further coil and condense around histone proteins to fit lots of information in a small space
• DNA is a very large molecule but the double helix structure allows it to condense and coil tightly