Biochemistry Chemicals of Life Important elements in Biology

Biochemistry Chemicals of Life

Important elements in Biology • CHONPS • carbon, hydrogen, oxygen, nitrogen, phosphorous, sulfur

Types of bonds • • Covalent – Strong bond formed when electrons are shared equally between atoms • Ionic – Bond formed between oppositely charged ions. Electron is gained by one of the atoms. • Hydrogen – weak bond formed by hydrogen atoms between molecules.

Water molecule (H 2 O) Polar molecule

Properties of Water due to its polarity • Cohesion: water molecules attracted to each other • Adhesion: water molecules attracted to other polar substances • Moderates temperature by absorbing heat

Enzymes • Protein catalyst that speed up chemical reactions in organisms. • Enzyme is not changed or consumed. • Specific for each substrate.

Acids Bases • A compound that releases H+ that releases - ions or OH ions in solution. + ions. accepts H • Ex. HCL – dissociates into • Ex. Na. OH – dissociates into H+ and Cl- ions. Na+ and OHions.

p. H scale • Measure of [H+] concentration in a solution. 0 7 acidic 14 neutral basic

Classification of molecules MOLECULE SUBUNIT Protein Carbohydrate ROLES / Diagram Amino acid Enzyme Structure Immunity Monosaccharide Short term energy storage Lipid Fatty acid Nucleic acid Nucleotide Phospholipid, fats, Insulation, oils Long term energy storage DNA/RNA Genetic

Proteins • Composed of amino acids. • CHON • Organisms use only 20 different amino acids. • Play important roles in: structure, movement, metabolism, transport, nutrition, defense.

Amino Acid

Carbohydrates • Major energy storage molecule for organisms. • Monosaccharides (simple sugars: glucose) • Disaccharides (double sugars: sucrose) • Animals store sugars in long chains with many branches: glycogen. • Plants store sugars in long chains: starch.

Lipids • Major component of cell membranes: phospholipid. • Long term energy storage: fat • Steroids and cholesterol

CHOOSE More Unsaturated Margarine (especially soft, light, trans fat free margarine) Oils: corn, canola, olive, safflower, soybean, sunflower AVOID More Saturated Butter Trans fat Some Solid peanut shortening butters Lard Fatback

Nucleic Acids • DNA - deoxyribonucleic acid - carries all of the genetic information of the cell. • RNA - ribonucleic acid - copies information on DNA, and carries the information for protein synthesis.

Phosphate Base Sugar