5.2 Respiration

• Which type of respiration requires oxygen?

  Aerobic
• Which type of respiration does not require oxygen?

  Anaerobic
• Which type of respiration produces less ATP?

  Anaerobic
• What is Glycolysis?

  Glycolysis is the splitting of one molecule of glucose (6 carbon) into two smaller molecules of pyruvate (3 carbon).
• Where does glycolysis occur?

  Glycolysis occurs in the cytoplasm.
• Glycolysis is the first stage of aerobic and anaerobic respiration and doesn't need oxygen to take place - it's an anaerobic process.
• Describe the process of glycolysis.

  1. Glucose is phosphorylated using a phosphate from a molecule of ATP to make a molecule of glucose phosphate and ADP.
  2. ATP is then used to add another phosphate: forming hexose bisphosphate.
  3. Hexose bisphosphate is then split into two molecules of triose phosphate.
  4. The triose phosphates are then oxidised to form two molecules of pyruvate.

  Overall 4 molecules of ATP and 2 molecules of NADH were formed. However, 2 molecules of ATP were using in stages 1 and 2 so there's a net gain of 2 molecules of ATP.