Statement not correct for hormones is that, these:

Options

A. Are not all protein
B. Are secreted in small amount
C. Affect metabolism
D. Acts as catalyst

Answer

To determine which statement is not correct regarding hormones, let's analyze each option step by step.

### Step 1: Analyze Option 1
**Statement**: "Not all hormones are proteins."
- **Explanation**: This statement is correct. Hormones can be classified into different categories, including steroid hormones, amine hormones, peptide hormones, protein hormones, glycoproteins, and eicosanoids. Therefore, it is true that not all hormones are proteins.

### Step 2: Analyze Option 2
**Statement**: "Hormones are secreted in small amounts."
- **Explanation**: This statement is also correct. Hormones are typically secreted in very small quantities, yet they can have significant effects on the body. This is a characteristic feature of hormones.

### Step 3: Analyze Option 3
**Statement**: "Hormones affect metabolism."
- **Explanation**: This statement is correct as well. Hormones play a crucial role in regulating metabolism. For example, thyroid hormones like thyroxine influence the basal metabolic rate of the body.

### Step 4: Analyze Option 4
**Statement**: "Hormones act as catalysts."
- **Explanation**: This statement is incorrect. Hormones do not act as catalysts. Catalysts are substances that increase the rate of a chemical reaction without being consumed in the process, which is not the function of hormones. Hormones primarily act as signaling molecules that regulate physiological processes.

### Conclusion
After analyzing all the options, the statement that is not correct regarding hormones is **Option 4: "Hormones act as catalysts."**

### Final Answer
The correct answer is **Option 4**.

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