BIOCHEMISTRY Chemistry of Life

Review of Chemistry Atom – neutral (protons, neutrons, & electrons) Atomic Number-# of protons (and # electrons) Atomic Mass - # protons + # neutrons Element – pure substance, one type of atom Molecule (covalently bonded compounds) Compound – 2 or more different elements together in a fixed ratio- H2O Bonds Ionic (Ions-charged atoms) * Covalent – sharing of electrons-strong * Hydrogen – weak bonds

ISOTOPES Different # of neutrons Different ATOMIC MASS Carbon 14 – Radioactive Carbon dating Molecular label (trace movement of substances in an organism). Cancer treatment Anti-bacterial - food treatment (prevent spoilage)

WATER Polar (Bear?)-uneven distribution of e- Oxygen – slight (–) charge Hydrogen – slight (+) charge “Mickey Mouse” Covalent bonds (within water molecule- H to O) Water to water molecules bonded together with : Hydrogen bonds Attraction of water molecules Adhesion – different substances (glass) – capillary action/meniscus Cohesion – same substance (water attracted to water) beads of water on car/penny Surface Tension (spiders/water striders/needle on water) “molecules on the surface of the liquid are not surrounded by like molecules on all sides, they are more attracted to other water molecules on the surface.”

WATER Boiling and melting/freezing points High specific heat (holds heat, more energy to raise temp.) Temperature (oC) Know: H2O: Boiling Point 100 oC Melting Pt. (Ice) 0 oC Body Temp. 37 oC Room Temp. 24 oC As freezes-less dense Mixture (physically mixed) Solution (mixture evenly distributed) Suspension (nondissolved) Solute – substance dissolved Solvent – substance – that dissolves solute WATER IS THE GREATEST SOLVENT The solvent of life!

Water is the solvent of life WATER IS THE UNIVERSAL SOLVENT (But oil/fats do not dissolve in water) Water properties support life Homeostasis: Better ability to resist temp. changes Cohesion & Adhesion Solvent Low Density of Ice

pH (factor of 10 – logarithmic) Acids (pH <7 – higher conc. of H+ ions than pure water) Bases (pH>7 – compound that produces OH- ions in a solution) Neutral 7 Buffer (weak acid/weak base – important in Human Body - 6.5-7.5 pH) Prevents sudden sharp pH changes Important in maintaining Homeostasis

Organic Chemistry Chemical compounds that contain CARBON and are essential to life. The study of all compounds – Bonds between Carbon atoms. C H O N P (S)

C 6 Carbon 12.011 An Element in the Periodic Table Section 2-1 Go to Section:

CARBON Essential Element for life C-12 Atomic # Atomic Mass Valence Electrons: e- available to form bonds Each valence e- can form a strong covalent bond Bond w/ C, H, O, N, P, S C-C bonds: single, double, triple, chains, rings

Macromolecules – “Giant molecules” Made of smaller molecules: monomers Monomers can be same or different Formed by polymerization Condensation (form polymer + Molecule of water) Vs. Hydrolysis (break down macromolecule-insertion of water)