Organic Compounds and Their Functions

Organic Compounds

• Organic compounds contain carbon, hydrogen, and often oxygen.
• Monomers are small molecules; polymers are large molecules made of monomers joined by covalent bonds.
• Dehydration synthesis creates polymers by removing water; hydrolysis breaks polymers into monomers by adding water.

Four Groups of Organic Molecules

• Carbohydrates: Elements C, H, O in a 1:2:1 ratio. Monomers are monosaccharides (simple sugars) like glucose. Examples include starch, cellulose, and glycogen. Functions include short-term energy storage.
• Lipids: Elements C, H, O, not in a 1:2:1 ratio; very little oxygen. Monomers are fatty acids. Polymers are triglycerides. Examples include fats, oils, waxes, steroids, and phospholipids. Functions include long-term energy storage and forming cell membranes.
• Proteins: Elements C, H, O, N (sometimes P & S). Monomers are amino acids (20 different types). Functions include structural support, enzymes (catalysts), and other bodily functions.
• Nucleic Acids: Elements C, H, O, N, P. Monomers are nucleotides (sugar, phosphate, and a nitrogenous base). Polymers are DNA and RNA. Examples are DNA and RNA. Functions include storing and transmitting genetic information.

Polymers Details

• Proteins: Polypeptides (amino acid chains) with primary, secondary, tertiary, and sometimes quaternary structures. Shape determines function. Denaturation changes shape with high temperature or pH.
• Nucleic Acids: Polynucleotides (nucleotides chains). DNA is a double helix with A-T and G-C base pairings, while RNA is a single strand with A-U, G-C pairings. DNA stores genetic information; RNA helps synthesize proteins.

Enzymes

• Enzymes are proteins that catalyze (speed up) biochemical reactions without being consumed.
• Enzymes are reusable.
• Active site: location where the substrate binds.
• Substrate: substance the enzyme acts upon.
• Shape & specificity: An enzyme is specific to its substrate and denatures with significant pH or temperature changes.