Para-thyroid hormone is a:

Options

A. peptide
B. carbohydrate
C. lipid
D. steroid

Answer

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

### Step 1: Identify the Source of Parathyroid Hormone
- Parathyroid hormone (PTH) is secreted by the parathyroid glands, which are located on the backside of the thyroid gland.

**Hint:** Look for the glands responsible for hormone secretion.

### Step 2: Determine the Type of Hormone
- Parathyroid hormone is classified as a peptide hormone. Peptide hormones are made up of amino acids and are typically water-soluble.

**Hint:** Recall the different types of hormones and their chemical structures.

### Step 3: Understand the Function of Parathyroid Hormone
- The primary function of parathyroid hormone is to regulate calcium levels in the blood. It increases the concentration of calcium ions by stimulating bone resorption, which releases calcium into the bloodstream.

**Hint:** Consider the physiological role of the hormone in the body.

### Step 4: Confirm the Classification
- Since parathyroid hormone is indeed a peptide hormone, we can confirm that the correct answer to the question is that parathyroid hormone is a peptide.

**Hint:** Review the characteristics that define peptide hormones.

### Final Answer:
Parathyroid hormone is a peptide hormone.