Feed back inhibition of enzyme action is affected by

Options

A. End product
B. Substrate
C. Enzyme
D. Rise in temperature

Answer

### Step-by-Step Solution:

1. **Understanding Feedback Inhibition**:
- Feedback inhibition is a regulatory mechanism in which the end product of a metabolic pathway inhibits an enzyme involved in its production. This process helps maintain homeostasis within the cell by preventing the overproduction of a substance.

2. **Mechanism of Feedback Inhibition**:
- In a typical scenario, an enzyme (let's call it Enzyme B) acts on a substrate (Substrate A) to produce a product (Product C).
- As Product C accumulates, it can bind to the enzyme or to a receptor that regulates the enzyme's activity.

3. **Role of Product Concentration**:
- The concentration of Product C is crucial. When the levels of Product C rise, it can signal the system to either stimulate or inhibit further production of Product C by affecting the activity of Enzyme B.
- If Product C binds to Enzyme B, it may inhibit its activity, reducing the conversion of Substrate A to Product C, thus preventing excessive accumulation of Product C.

4. **Example of Feedback Inhibition**:
- A classic example is the hormone oxytocin during childbirth. The contractions of the uterus stimulate the release of more oxytocin, which further enhances contractions. This is a positive feedback mechanism.
- However, in terms of feedback inhibition, when a product reaches a certain level, it can inhibit the enzyme responsible for its production, thereby regulating the process.

5. **Conclusion**:
- Feedback inhibition is primarily affected by the concentration of the end product (Product C) and its interaction with the enzyme (Enzyme B). The feedback mechanism can either stimulate or inhibit enzyme activity based on the needs of the cell.