18 - respiration

Question 1

What are the 4 main steps of glycolysis?

Answer 1

1. Phosphorylation- requires 2 molecules of ATP, two phosphates are released from the 2 ATP molecules and are attached to a glucose molecule forming hexose bisphosphate.
2. Lysis- This destabilises the molecule causing it to split into 2 triose phosphate molecules.
3. Phosphorylation- another phosphate is added to each TP, forming 2 triose bisphosphate molecules. These phosphate groups cone from the free inorganic phosphate ions present in the cytoplasm.
4. Dehydrogenation and formation of ATP- The 2 triose bisphosphate molecules are then oxidised by the removal of hydrogen atoms to form 2 pyruvate molecules. NAD coenzymes accept the removed hydrogens- they are reduced- forming 2 NADH molecules.
   At the same time, 4 ATP molecules are produced using phosphates from the triose bisphosphate molecules.