Glycolysis

• Glycolyis involves splitting one molecule of glucose (6C) into two smaller molecules of pyruvate (3C) which happens in the cytoplasm of cells.
• Glycolysis is the first stage of both aerobic and anaerobic respiration and doesn't need oxygen to take place - so it's an anaerobic process.
• There are two stages in glycolysis - First ATP is used to phosphorylate glucose to triose phosphate. Then triose phosphate is oxidised, releasing ATP. Overall there is a net gain of 2 ATP.
• (1) Stage 1 - Phosphorylation

  1. Glucose is phosphorylated by adding 2 phosphates from 2 molecules of ATP
  2. This creates 1 molecules of hexose bisphosphate and 2 molecules of ADP
  3. Hexose bisphosphate is split up into 2 molecules of triose phosphate.
• Stage Two - Oxidation

  1. Triose phosphate is oxidised (loses hydrogen) forming 2 molecules of pyruvate.
  2. NAD collects the hyfrogen ions forming 2 NADH
  3. 4 ATP are produced, but 2 were used up in stage one, so there's a net gain of 2 ATP.