Which amino acid is required for synthesis of catecholamines ?

Options

A. Glycine
B. Cystine
C. Arginine
D. Tyrosine

Answer

**Step-by-Step Solution:**

1. **Identify the Hormones**: Understand that catecholamines include hormones such as epinephrine (adrenaline) and norepinephrine (noradrenaline), which are produced in the adrenal medulla.

2. **Understand the Source**: Recognize that the adrenal glands, located on top of the kidneys, consist of two main parts: the adrenal cortex and the adrenal medulla. The medulla is responsible for producing catecholamines.

3. **Determine the Amino Acid**: Among the amino acids listed (Glycine, Cysteine, Arginine, and Tyrosine), we need to identify which one is specifically involved in the synthesis of catecholamines.

4. **Recall the Role of Tyrosine**: Tyrosine is known to be a precursor in the synthesis of catecholamines. It is converted into L-DOPA, which is then converted into dopamine, and subsequently into norepinephrine and epinephrine.

5. **Conclude the Answer**: Therefore, the amino acid required for the synthesis of catecholamines is **Tyrosine**.

**Final Answer**: Tyrosine

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