Biology- DNA

View mindmap
  • DNA
    • Made up of monomers called nucleotide
      • this has 3 parts: Phosphate, Deoxyribose (sugar) and a base
        • There are 4 different bases in DNA these are: Adenine, Thymine, Guanine and Cytosine
          • Adenine pairs with Thymine
          • Guanine pairs with Cytosine
    • Has 2 polynucleotide strands twisted around each other to form a Double Helix
      • Hydrogen bonds between bases= weak. So the double helix protects the bonds in the centre of the molecule. so the code isn't corrupted
    • How does the structure relates to function?
      • Long= store lots of information
      • Complementary base pairs= replicates accurately
      • Base pairs protected inside by sugar phosphate backbone= stable
      • Weak hydrogen bonds= replicates by strands unzipping
    • Semi conservative replication
      • Step 1: Hydrogen bonds broken by an enzyme
      • Step 2: Strands separate exposing bases but strands are kept intact
      • Step3: DNA polymerase enzyme attaches free nucleotides to exposed bases
      • Step 4: New strand is built on original strands as the complementary bases fit together
      • Is where one strand in each molecule contains the original parent strand and a newly synthesised strand


No comments have yet been made

Similar Human Biology resources:

See all Human Biology resources »See all Human, animal and plant physiology resources »