Amino acids are mostly synthesized from

Options

A. Mineral salts
B. Fatty acids
C. Volatile acids
D. `alpha` - ketoglutaric acid

Answer

**Step-by-Step Solution:**

1. **Understanding Amino Acids**: Amino acids are organic compounds that serve as the building blocks of proteins. They play a crucial role in various biological processes.

2. **Identifying Precursors**: To synthesize amino acids, organisms utilize various precursors. The question provides four options: mineral salt, fatty acid, volatile acid, and alpha-ketoglutaric acid.

3. **Role of Alpha-Ketoglutaric Acid**: Alpha-ketoglutaric acid is an important intermediate in the Krebs Cycle (also known as the Citric Acid Cycle). This cycle is essential for cellular respiration and energy production.

4. **Conversion to Amino Acids**: Alpha-ketoglutaric acid can be converted into amino acids, specifically glutamic acid. This conversion is significant because glutamic acid is a key amino acid that can further participate in the synthesis of other amino acids.

5. **Conclusion**: Given that alpha-ketoglutaric acid is a precursor for amino acids and plays a vital role in their synthesis, the correct answer to the question is that amino acids are mostly synthesized from alpha-ketoglutaric acid.

**Final Answer**: Amino acids are mostly synthesized from alpha-ketoglutaric acid.

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