Short Answer Questions - Formation of ATP: oxidation and reduction reactions
1. NADPH + H+ can be oxidised to form ATP in the respiratory chain. True or false?
False. NADPH + H+ is used for biosynthetic reactions, e.g. fatty acid synthesis.
2. FAD is not a prosthetic group. True or false?
False. FAD is a prosthetic group: it is covalently bound to an enzyme, as opposed to NAD+ which is free to dissociate from its binding site.
3. Oxygen is essential for the biosynthesis of ATP. True or false?
False. ATP can be made by anaerobic reactions, eg substrate-level phosphorylation, creatine phosphate and myokinase reactions.
4. The flow of electrons along the electron transport chain causes the F1 complex to form ATP. True or false?
False. It is the flow of protons which causes the F1 complex to form ATP.
5. When NADH + H+ is formed in the cytosol it must be transported into the mitochondrion for oxidation in the respiratory chain to form ATP. True or false?
True. The respiratory chain is located in the inner membrane of the mitochondrion.
6. Both membranes of the mitochondrion are freely permeable to NADH + H+. True or false?
False. The outer membrane of the mitochondrion is freely permeable to NADH + H+. However, to cross the inner membrane, NADH + H+ needs either the malate/aspartate shuttle or the glycerol 3-phosphate shuttle.
7. The red blood cell (which does not contain mitochondria) cannot make ATP. True or false?
False. ATP is made by anaerobic glycolysis.
8. Lactate formed during anaerobic glycolysis (e.g. in muscle) is a toxic waste product which is excreted in the urine. True or false?
False. Lactate is returned to the liver and recycled to form glucose (or glycogen) by the Cori cycle.
