Amino acids are needed in the body for the synthesis of various other products .Taking this into consideration; the amino acid tryptophan is the precursor for the synthesis of

Options

A. thyroxine and tri-iodothyronine
B. oestrogen and progesterone
C. cortisol and cortisone
D. melatonin and serotonin

Explanation

**Step-by-Step Solution:**

1. **Understanding the Role of Amino Acids:**
- Amino acids are the building blocks of proteins and are essential for the synthesis of various biomolecules in the body, including hormones and neurotransmitters.

2. **Identifying Tryptophan:**
- Tryptophan is an essential amino acid that serves as a precursor for several important compounds in the body.

3. **Exploring Potential Products:**
- The question asks for the specific products synthesized from tryptophan. We need to evaluate the options provided.

4. **Evaluating Hormones:**
- The options include:
- Estrogen
- Progesterone
- Cortisol
- Thyroxine
- Triiodothyronine
- Melatonin
- Serotonin

5. **Analyzing Each Option:**
- **Estrogen and Progesterone:** These are steroid hormones synthesized from cholesterol, not amino acids. Therefore, they cannot be synthesized from tryptophan.
- **Cortisol:** This is also a steroid hormone derived from cholesterol, making it another incorrect option.
- **Thyroxine and Triiodothyronine:** These hormones are derived from the amino acid tyrosine, not tryptophan, so they are also incorrect.
- **Melatonin and Serotonin:** Both of these are derived from tryptophan. Serotonin is a neurotransmitter, and melatonin is a hormone that regulates sleep-wake cycles.

6. **Conclusion:**
- The correct answer is that tryptophan is the precursor for the synthesis of **melatonin and serotonin**.

**Final Answer:**
Tryptophan is the precursor for the synthesis of **melatonin and serotonin**.

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