gen-define-vitamins-and-their-functions-and-give-one-short-worke-2e92

Define vitamins and their functions and give one short worked example.

# Vitamins: Definition and Functions ## Definition **Vitamins** are organic compounds required by the body in small amounts that cannot be synthesized in sufficient quantities and must be obtained through diet. They are essential for normal growth, development, and metabolic processes. ## Functions Vitamins serve several critical functions: 1. **Coenzymes/Cofactors** - Assist enzymes in biochemical reactions 2. **Antioxidants** - Protect cells from oxidative damage 3. **Gene regulation** - Control protein synthesis 4. **Structural support** - Maintain tissues (bones, skin, blood) 5. **Energy metabolism** - Help convert food into energy ## Classification - **Fat-soluble**: A, D, E, K (stored in body fat) - **Water-soluble**: B-complex, C (not stored; excess excreted) --- ## Worked Example: Vitamin C (Ascorbic Acid) **Function**: Essential for collagen synthesis and acts as an antioxidant **Problem**: A sailor on a 6-month voyage consumes no fresh fruits or vegetables. What deficiency disease might develop and why? **Solution**: - **Disease**: Scurvy - **Mechanism**: Without vitamin C, the enzyme prolyl hydroxylase cannot function properly - This enzyme is needed to hydroxylate proline residues in collagen - **Result**: Defective collagen leads to: - Bleeding gums - Poor wound healing - Weakened blood vessels **Prevention**: Daily intake of 75-90mg vitamin C from citrus fruits, vegetables, or supplements.