Statement not correct for hormones is that they

Options

A. Are not all protein
B. Are secreted is small amount
C. affect metabolism
D. Acts as catalysts

Answer

To determine which statement about hormones is incorrect, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Identify the Statements**: We need to evaluate the statements regarding hormones to find the one that is incorrect. The statements are:
- Option 1: Hormones are not all proteins.
- Option 2: Hormones are secreted in small amounts.
- Option 3: Hormones affect metabolism.
- Option 4: Hormones act as catalysts.

2. **Evaluate Option 1**:
- **Analysis**: Not all hormones are proteins. Hormones can be classified into different types, including peptide (protein) hormones and steroid (lipid-derived) hormones.
- **Conclusion**: This statement is correct.

3. **Evaluate Option 2**:
- **Analysis**: Hormones are indeed secreted in very small amounts into the bloodstream. This is a characteristic feature of hormones, as they are effective in low concentrations.
- **Conclusion**: This statement is correct.

4. **Evaluate Option 3**:
- **Analysis**: Hormones do affect metabolism. For example, Thyroxine regulates the basal metabolic rate in the body.
- **Conclusion**: This statement is correct.

5. **Evaluate Option 4**:
- **Analysis**: Hormones do not act as catalysts. Catalysts are typically enzymes that speed up chemical reactions, whereas hormones are signaling molecules that regulate physiological processes.
- **Conclusion**: This statement is incorrect.

6. **Final Answer**: The statement that is not correct regarding hormones is that they "act as catalysts."

### Summary:
The incorrect statement about hormones is that they act as catalysts. Hormones are signaling molecules that regulate various functions in the body, but they do not function as catalysts like enzymes do.