Session 3

Question 1

Differences between oxidative and substrate level phosphorylation

Answer 1

Oxidative requires membrane associated complexes (inner mitochondrial membrane) - substrate requires soluable enzymes (cytoplasm and mitochondrial matrix)

• ox - energy coupling occures indirectly through generation and subsequent utilisation of protein gradient (pmf) sub - energy coupling occures directly though formation of a high energy of hydrolysis bond.
• ox cannot occure in absence of oxygen - sub can occure in limited oxygen

Ox - major process for ATP synthesis in cells that require large amounts of energy - sub - minor process for ATP synthesis in cells that require large amounts of energy