Structure, properties, functions, and importance

1. Carbohydrates

1. Carbohydrates are organic molecules consisting of carbon (C), hydrogen (H), and oxygen (O) in the general formula (CH₂O)_n.
2. They are classified into monosaccharides, disaccharides, and polysaccharides.
3. Monosaccharides include glucose, fructose, and galactose.
4. Disaccharides include sucrose (glucose + fructose), lactose (glucose + galactose), and maltose (glucose + glucose).
5. Polysaccharides include starch, cellulose, and glycogen.
6. Glucose (C₆H₁₂O₆) is the primary energy source for cells.
7. Starch is the storage carbohydrate in plants, while glycogen is the storage carbohydrate in animals.
8. Cellulose, found in plant cell walls, is indigestible for humans but provides dietary fiber.
9. Functions: Provide energy, serve as structural components, and aid in biological recognition processes.
10. Excess carbohydrates are converted to fat and stored in the body.

2. Proteins

1. Proteins are polymers of amino acids linked by peptide bonds.
2. They contain carbon (C), hydrogen (H), oxygen (O), nitrogen (N), and sometimes sulfur (S).
3. Amino acids are classified as essential (must be obtained from food) and non-essential (synthesized by the body).
4. Examples of essential amino acids: lysine, methionine, leucine.
5. Structure of Proteins: Primary (sequence of amino acids), Secondary (alpha-helix, beta-sheet), Tertiary (3D folding), and Quaternary (multiple polypeptide chains).
6. Functions: Structural support (collagen), enzymatic activity (enzymes), transport (hemoglobin), defense (antibodies), and hormonal regulation (insulin).
7. Denaturation is the loss of protein structure due to heat, pH changes, or chemicals.
8. Protein deficiency can lead to disorders like kwashiorkor and marasmus.

3. Fats (Lipids)

1. Fats, also called lipids, are composed of glycerol and fatty acids.
2. They are classified into saturated and unsaturated fats.
3. Saturated fats (found in butter, cheese) contain no double bonds and are solid at room temperature.
4. Unsaturated fats (found in oils, nuts) contain one or more double bonds and are liquid at room temperature.
5. Trans fats are artificially hydrogenated fats that are harmful to health.
6. Phospholipids are essential components of cell membranes.
7. Functions: Provide energy, act as insulation, protect organs, and play a role in hormone production.
8. Cholesterol is a lipid that is essential for cell membranes but can lead to heart disease if levels are too high.

4. Importance of Biomolecules in Daily Life

1. Carbohydrates provide quick energy (e.g., rice, bread, fruits).
2. Proteins are necessary for growth, muscle repair, and enzymatic functions (e.g., eggs, meat, beans).
3. Fats are vital for long-term energy storage and cellular functions (e.g., olive oil, nuts, dairy products).
4. A balanced diet includes appropriate amounts of carbohydrates, proteins, and fats for proper health.