Which of the following hormones is derived from a single amino acid?

Options

A. thyroxine
B. oxytocin
C. estradiol
D. epinephrine

Answer

To determine which hormone is derived from a single amino acid, we can follow these steps:

### Step 1: Understand the Types of Hormones
Hormones can be classified based on their chemical structure. The main categories include:
- Protein hormones
- Steroid hormones
- Iodothyronin hormones
- Amino acid derivative hormones

### Step 2: Analyze the Options
We have four options to consider:
1. Thyroxine
2. Oxytocin
3. Estradiol
4. Epinephrine

### Step 3: Identify the Source of Each Hormone
- **Thyroxine**: This hormone is classified as an iodothyronin hormone and is not derived from a single amino acid.
- **Oxytocin**: This is a peptide hormone (protein hormone) that is secreted by the hypothalamus and is not derived from a single amino acid.
- **Estradiol**: This is a steroid hormone derived from cholesterol, not from a single amino acid.
- **Epinephrine**: This hormone is derived from the amino acid tyrosine and is classified as an amino acid derivative hormone.

### Step 4: Conclusion
Based on the analysis, the hormone that is derived from a single amino acid is **epinephrine**.

### Final Answer
Epinephrine is the hormone derived from a single amino acid.

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