Which of the following statements is not correct?

Options

A. Ovalbumin is a simple food reserve in egg-white.
B. Blood proteins thrombin and fibrinogen are involved in blood clotting.
C. Denaturation makes the proteins more active.
D. Insulin maintains sugar level in the blood of a human body.

Explanation

To solve the question, we need to evaluate each of the provided statements and identify which one is not correct.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- **Statement:** "Ovalbumin is a simple food reserve in the egg white."
- **Analysis:** This statement is correct. Ovalbumin is indeed a storage protein found in egg white and serves as a food reserve.

2. **Evaluate the Second Statement:**
- **Statement:** "Blood proteins thrombin and fibrinogen are involved in blood clotting."
- **Analysis:** This statement is also correct. Thrombin is an enzyme that converts fibrinogen into fibrin, which is essential for blood clotting.

3. **Evaluate the Third Statement:**
- **Statement:** "Denaturation makes the protein more active."
- **Analysis:** This statement is incorrect. Denaturation involves the disruption of a protein's structure (secondary, tertiary, and quaternary), which leads to a loss of its biological activity. Therefore, denaturation does not make proteins more active; it actually deactivates them.

4. **Evaluate the Fourth Statement:**
- **Statement:** "Insulin maintains sugar level in blood of human body."
- **Analysis:** This statement is correct. Insulin is a hormone that helps regulate blood sugar levels by facilitating the uptake of glucose by cells.

### Conclusion:
The statement that is not correct is the third one: "Denaturation makes the protein more active."

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