Golden Key Points-Chapter 9-Biomolecules

Golden Key Points

1. Chemical Composition Analysis:

• Living tissues contain a variety of organic and inorganic compounds.
• Chemical analysis involves separating compounds into acid-soluble and acid-insoluble fractions.
• Elemental analysis reveals the elemental composition, while compound analysis identifies specific organic and inorganic constituents.
• Organic compounds include amino acids, nucleotide bases, fatty acids, etc.

2. Lipids:

• Lipids are generally water-insoluble compounds found in living organisms.
• They include simple fatty acids, glycerol esters (monoglycerides, diglycerides, triglycerides), phospholipids, and more complex structures.
• Lipids play roles in energy storage, membrane structure, and signaling.

3. Primary and Secondary Metabolites:

• Primary metabolites are essential for basic physiological functions, while secondary metabolites are produced by plants, fungi, and microbes and often have ecological or industrial significance.
• Secondary metabolites include alkaloids, flavonoids, essential oils, pigments, etc.

4. Biomacromolecules:

• Biomolecules in living tissues can be classified based on molecular weight into micromolecules (less than 1000 daltons) and macromolecules (over 10000 daltons).
• Macromolecules include proteins, nucleic acids, polysaccharides, and lipids (in some cases).
• Polysaccharides are long chains of sugars, while nucleic acids are polynucleotides composed of nucleotides.

5. Proteins:

• Proteins are polypeptides consisting of amino acid chains.
• They have primary, secondary, tertiary, and quaternary structures, which determine their functions.
• Proteins serve various roles, including enzymatic catalysis, structural support, and signaling.

6. Enzymes:

• Enzymes are proteins that catalyze biochemical reactions by lowering activation energy.
• They have specific active sites where substrates bind, forming enzyme-substrate complexes.
• Enzyme activity is influenced by factors such as temperature, pH, substrate concentration, and the presence of inhibitors.

7. Chemical Reactions:

• Chemical reactions involve the breaking and forming of chemical bonds.
• Enzymes catalyze reactions, increasing reaction rates by lowering activation energy.
• The rate of a reaction is influenced by factors such as temperature, pH, substrate concentration, and the presence of catalysts or inhibitors.

8. Nature of Enzyme Action:

• Enzyme action involves the formation of enzyme-substrate complexes, catalyzing the conversion of substrates into products.
• The catalytic cycle includes substrate binding, induced fit, catalysis, and product release.

9. Factors Affecting Enzyme Activity:

• Enzyme activity is affected by temperature, pH, substrate concentration, and the presence of specific chemicals (inhibitors or activators).
• Each enzyme has an optimum temperature and pH for maximum activity.
• Substrate concentration affects enzyme activity up to a point of saturation (Vmax).

10. Classification and Nomenclature of Enzymes:

• Enzymes are classified into six main classes based on the type of reactions they catalyze.
• Each class is further divided into subclasses, and enzymes are named using a four-digit number system.
• The six classes include oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases.

11. Co-factors:

• Cofactors are non-protein constituents required for enzyme activity.
• Three types of cofactors include prosthetic groups (tightly bound organic compounds), coenzymes (transiently associated organic compounds), and metal ions (required for catalytic activity).
• Cofactors are essential for the catalytic function of enzymes.