Question

The key enzymes in metabolic pathways are under regulatory control. Why is the level of citrate of significance in controlling the breakdown of glucose in the cell. What impact does it have on cell metabolism when compared to that of NADH ? (10 marks)

Answer 1

Explanation: The level of citrate is important in controlling the breakdown of glucose because it regulates key enzymes involved in glucose metabolism. High levels of citrate inhibit enzymes in glycolysis, slowing down glucose breakdown. Citrate also activates fatty acid synthesis.

On the other hand, NADH plays a crucial role in energy production. It carries high-energy electrons and contributes to ATP production. High levels of NADH can inhibit enzymes in glycolysis and the citric acid cycle, affecting energy production.

In summary, citrate controls glucose breakdown directly, while NADH impacts metabolism through its involvement in energy production and feedback regulation of metabolic pathways.