Insulin by chemical nature is :

Options

A. Carbohydrate
B. Protein
C. Steroid
D. lipid

Answer

To determine the chemical nature of insulin, we can follow these steps:

### Step 1: Understand the Classification of Hormones
Hormones are classified based on their chemical structure into three main categories: peptide hormones (or protein hormones), steroid hormones, and amino acid derivatives.

### Step 2: Identify Insulin's Category
Insulin is produced by the pancreas and is known to be a peptide hormone. This means it is made up of amino acids and falls under the category of protein hormones.

### Step 3: Compare with Other Hormone Types
- **Carbohydrates**: These are sugars and starches; insulin is not a carbohydrate.
- **Steroid Hormones**: These are derived from cholesterol and include hormones like cortisol and testosterone; insulin is not a steroid.
- **Lipid Hormones**: These are primarily fats; insulin does not belong to this category.

### Step 4: Conclusion
Since insulin is a peptide hormone, it is classified as a protein hormone. Therefore, the correct answer to the question is that insulin by chemical nature is a **protein**.

### Final Answer
Insulin by chemical nature is a **protein**.

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