Which of the following is TRUE about feedback inhibition?

• A. Feedback inhibition has no physiological importance.
• B. Multiple products are required for feedback inhibition.
• C. Feedback inhibition of a pathway can only be accomplished by the products of that pathway.
• D. Feedback inhibition involves products binding to the active site to prevent enzyme activity.

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the concept of feedback inhibition. Feedback inhibition is a regulatory mechanism in which the end product of a metabolic pathway inhibits an enzyme involved in the pathway, thus controlling the production of the product.
2. Step 2: Clarify the physiological importance of feedback inhibition. Feedback inhibition is crucial for maintaining homeostasis within cells by preventing the overproduction of substances and conserving energy.
3. Step 3: Evaluate the statement about multiple products. Feedback inhibition typically involves a single end product that inhibits an enzyme, not multiple products.
4. Step 4: Analyze the statement regarding the binding site. Feedback inhibition usually involves the end product binding to an allosteric site, not the active site, to change the enzyme's shape and reduce its activity.
5. Step 5: Consider the statement about pathway products. Feedback inhibition is indeed accomplished by the products of the pathway, as they regulate the pathway's activity by inhibiting enzymes involved in earlier steps.