Feed back inhibition is due to accumulation of

Options

A. Substrates
B. Products
C. Metal ions
D. Pathogens

Answer

### Step-by-Step Solution:

1. **Understanding Feedback Inhibition**: Feedback inhibition is a regulatory mechanism in biochemical pathways. It occurs when the end product of a metabolic pathway inhibits an enzyme that acts earlier in the pathway.

2. **Identifying the Role of Products**: In feedback inhibition, the accumulation of the end product (or products) of a metabolic pathway sends a signal to the enzyme that catalyzes the first step of the pathway to reduce or halt its activity. This prevents the overproduction of the end product.

3. **Analyzing the Options**:
- **Substrate**: This is the starting material for an enzyme-catalyzed reaction and does not cause inhibition.
- **Products**: These are the end results of the enzymatic reactions and are responsible for feedback inhibition.
- **Metal Ions**: These can act as cofactors for enzymes but are not directly involved in feedback inhibition.
- **Pathogens**: These are disease-causing agents and are unrelated to the concept of feedback inhibition.

4. **Conclusion**: The correct answer to the question is that feedback inhibition is due to the accumulation of **products**.

### Final Answer:
Feedback inhibition is due to the accumulation of **products**.

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