Feed back inhibition is affected by

Options

A. End Product
B. First Product
C. Enzymes
D. Extemal factors

Answer

### Step-by-Step Solution:

1. **Understanding Feedback Inhibition**:
- Feedback inhibition is a regulatory mechanism in enzymatic reactions where the accumulation of an end product inhibits the enzyme's activity. This prevents the overproduction of the product.

2. **Normal Enzymatic Reaction**:
- In a typical enzymatic reaction, a substrate binds to an enzyme, forming an enzyme-substrate complex. This complex undergoes a reaction to produce an end product, which is then released, allowing the enzyme to be reused.

3. **Role of Product Concentration**:
- As the reaction proceeds, the concentration of the product increases while the substrate concentration decreases. When the product reaches a certain level, it signals the enzyme to slow down or stop its activity.

4. **Mechanism of Feedback Inhibition**:
- The enzyme senses the high concentration of the product. When the product levels are high, the enzyme becomes inactive or less active, reducing further production until the product is utilized and its concentration decreases.

5. **Dependence on End Product**:
- Feedback inhibition is specifically dependent on the concentration of the end product, not the substrate. Even if there is an abundance of substrate, the enzyme will remain inactive if the product concentration is high.

6. **Conclusion**:
- Therefore, feedback inhibition is primarily affected by the end product of the enzymatic reaction.

### Final Answer:
Feedback inhibition is affected by the **end product** of the enzymatic reaction.

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