Biochemistry - Molecules of Life

Biochemistry: Molecules of Life

Atoms and Molecules of Life

  • Organic Compounds: Contain carbon, derived from living organisms.
  • Inorganic Compounds:
    • No living origin, don’t contain carbon.
    • Simple molecules or elements.
    • Examples include water, minerals.
  • Role of Enzymes: Catalysts in biochemical reactions.

Inorganic Compounds

  • Water: Most important, used as a solvent, regulates temperature, and provides structure.

Minerals

Macronutrients

  • Calcium (Ca): Strong bones, blood coagulation.
  • Phosphorus (P): Bone strength, component of ATP/RNA.
  • Sodium (Na): Water balance, muscle contraction.
  • Potassium (K): Regulates heart rate, fluid balance.

Micronutrients

  • Iron (Fe): Forms hemoglobin, oxygen transport.
  • Iodine (I): Thyroid hormone regulation.

Acids, Bases, and pH

  • pH scale:
    • Acidic: 0 - 6.9
    • Neutral: 7
    • Alkaline: 7.1 - 14
  • Digestive Conditions:
    • Gastric juices: Acidic
    • Intestinal juices: Alkaline

Organic Compounds

  • Types: Carbohydrates, fats, proteins (polymers made from monomers).

Carbohydrates

  • Monosaccharides: Basic units (e.g., glucose, fructose, galactose).
  • Disaccharides: Formed by two monosaccharides (e.g., sucrose, maltose, lactose).
  • Polysaccharides: Long chains (e.g., starch in plants, glycogen in animals).

Food Tests for Carbohydrates

  • Iodine Test: Blue-black indicates starch.
  • Benedict's Test: Green to brick-red indicates sugars.

Fats and Lipids

  • Composition: 1 glycerol and 3 fatty acids.
  • Properties: Used for energy storage, insulation.
  • Test for Fats: Ether test for cloudy emulsion.

Proteins

  • Functions: Structure, transport (hemoglobin), protection (antibodies).
  • Building Blocks: Amino acids linked by peptide bonds.
  • Food Tests for Proteins: Biuret test for lilac-purple.

Enzymes

  • Definition: Biological catalysts made of proteins.
  • Functionality: Sensitive to temperature; optimal at 35-40°C. Denatured above 45°C.
  • Lock and Key Theory: Substrate fits into enzyme's active site, forming an enzyme-substrate complex.