DNA

• DNA


  Made up of individual units called nucleotides, each consisting of a sugar molecule, a phosphate molecule and a base
• DNA molecule structure

  1. Sugar and phosphate molecules form a backbone

  2. 2 bases pair up to form the rungs of the ladder
• DNA bases

  • Adenine
  • Guanine
  • Thymine
  • Cytosine
• DNA base pairing

  A always pairs with T, C always pairs with G
• DNA molecule


  Two strands coiled together in a double helix shape
• DNA


  A code, the sequence of A, T, C and G codes for different proteins
• Proteins coded for by DNA

  • Enzymes
  • Hormones such as insulin
  • Antibodies for immunity
  • Structures such as hair and nails
• Living organisms are essentially just a bunch of proteins
• Proteins


  Made up of smaller subunits called amino acids
• Genetic code


  3 different bases code for each amino acid
• Mutation

  A rare and random change to an organism's DNA base sequence that can be inherited
• Change in DNA base sequence (mutation)


  Could result in a different amino acid and therefore a different protein
• DNA is the genetic material that contains instructions for making proteins.
• Nitrogenous bases pair up according to complementary base pairs (C with G, A with T), holding the two strands of DNA together.