Chemical Basis of Life Basic Chemistry – matter, energy, chemical bonds & reactions Biochemistry – inorganic compounds – organic compounds

Organic vs Inorganic Compounds Organic molecules: – contain carbon – usually larger than inorganic molecules – dissolve in water & organic liquids – carbohydrates, proteins, lipids, & nucleic acids Inorganic molecules – do not contain carbon – smaller than organic molecules – dissociate in water, forming ions – water, oxygen, carbon dioxide, & inorganic salts

Inorganic Compounds Water (H 2 O): - high heat capacity - high heat of vaporization - polar solvent properties - reactivity Oxygen (O 2 ): - used by organelles to release energy from nutrient molecules - drive cell’s metabolic activities - necessary for survival

Acid-Base Concentrations pH scale: indicates the [ ] of hydrogen ions in solution Neutral: pH 7; indicates equal [ ] of H + & OH - Acidic : pH less than 7; indicates a greater [ ] of H + Basic : pH greater than 7; indicates a greater [ ] of OH -

contain C, H, and O ratio of H to O is to 2:1 (C 6 H 12 O 6 ) provide energy to cells supply materials to build cell structures water-soluble monosaccharides – glucose, fructose disaccharides – sucrose, lactose polysaccharides – glycogen, cellulose Carbohydrates

Soluble in organic solvents; insoluble in water Triglycerides (neutral fats) used primarily for energy; most common lipid in the body contain C, H, & O but less O than carbohydrates (C 57 H 110 O 6 ) building blocks are 1 glycerol & 3 fatty acids/molecule saturated & un- - mono - poly - trans fats -  -3 fatty acids Lipids (fats)

Building blocks are 1 glycerol, 2 fatty acids, and 1 phosphate per molecule Hydrophilic and hydrophobic properties Major component of cell membranes Phospholipids

Four connected rings of carbon Widely distributed in the body w/ various functions  component of cell membrane  used to synthesize hormones  cholesterol – most important molecule Steroids

Proteins Amino acids: building blocks of protein –2 functional groups: amine (- NH 2 ) & acid group (-COOH) –act as a base or acid –differences based on R group –Peptide bond: amino end of one AA linked to carboxyl end of another  polypeptide –most proteins are macromolecules (b/t 100 – 10,000 AA)

Enzymes & Enzymatic Activity Proteins that act as biological catalysts: –Regulate & accelerate chemical reactions –Chemically specific Mechanism of enzyme action: –substrate binding –internal rearrangement –enzyme dissociation

Nucleotide Nucleotide : single nitrogenous base together w/ a sugar (deoxyribose) & a phosphate group - basic unit of DNA Deoxyadenylic acid

Comparison of DNA & RNA nucleic acids DNA RNA nitrogenous bases guanine………cytosine cytosine………guanine adenine……….uracil thymine………adenine sugar-phosphate deoxyribose ribose groups strands of double single nucleotides

Adenosine Triphosphate - Energy currency of the cell - ribonucleotide w/ 2 extra phosphates - ATP hydrolysis - ATP phosphorylation ATP  ADP + Pi + energy