Which is a typical example of 'feedback inhibition'?

Explanation

The correct answer is: Allosteric inhibition of hexokinase by glucose 6­-phosphate.Feedback inhibition is a regulatory mechanism in which the end product of a metabolic pathway inhibits an earlier step in that pathway. It helps maintain homeostasis by preventing excessive production of a particular molecule. In this case, hexokinase is an enzyme involved in the first step of glucose metabolism, where it converts glucose into glucose 6-phosphate. Glucose 6-phosphate is further processed in various metabolic pathways.Glucose 6-phosphate acts as an allosteric inhibitor of hexokinase, meaning it binds to a specific site on the enzyme and causes a conformational change that reduces its catalytic activity. This inhibition occurs when the concentration of glucose 6-phosphate is high, indicating that there is already sufficient glucose 6-phosphate present in the cell. By inhibiting hexokinase, the production of additional glucose 6-phosphate is slowed down, preventing an excess accumulation of this metabolite.The other options provided in the question are not examples of feedback inhibition:Cyanide and cytochrome reaction: Cyanide is a potent inhibitor of cytochrome enzymes, which are involved in cellular respiration. However, this is not an example of feedback inhibition because it does not involve the end product of a metabolic pathway regulating an earlier step. Sulpha drugs and folic acid synthesizer bacteria: Sulpha drugs are antibiotics that inhibit the growth of bacteria by interfering with their ability to synthesize folic acid. While this is a form of inhibition, it does not involve feedback regulation or the end product of a metabolic pathway. The reaction between succinic dehydrogenase and succinic acid: This option is not an example of feedback inhibition. Succinic dehydrogenase (also known as succinate dehydrogenase) is an enzyme involved in the citric acid cycle, and its reaction with succinic acid is a normal part of the metabolic pathway. However, it does not involve the end product of the pathway inhibiting an earlier step.