1. MOVING FROM ECOLOGY TO BIOCHEMISTRY

2. BIOCHEMISTRY LEVELS OF ORGANIZATION Organisms Organ Systems OrgansTissues CellsMoleculesAtoms Subatomic Particles

3. BIOLOGICAL BONDS (CONCEPT 2.3) TYPES OF BONDS & INTERACTIONS COVALENT BONDS IONIC BONDS HYDROGEN BONDS HYDROPHOBIC & HYDROPHILIC INTERACTIONS VAN DER WAALS INTERACTIONS

4. COVALENT BONDS VALENCE ELECTRONS ARE SHARED BY TWO ATOMS THERE ARE TWO TYPES POLAR – SHARED UNEQUALLY NONPOLAR – SHARED EQUALLY (O=O, H-H)

5. IONIC BONDS SOME ATOMS ATTRACT VALENCE ELECTRONS SO UNEQUALLY THAT THE MORE ELECTRONEGATIVE ATOM STEALS THE ELECTRON AWAY FROM THE LESS ELECTRONEGATIVE

6. HYDROGEN BONDS THE SLIGHTLY POSITIVE HYDROGEN ATOM OF A POLAR MOLECULE IS ATTRACTED TO THE SLIGHTLY NEGATIVE ATOM OF ANOTHER MOLECULE WATER IS POLAR

7. HYDROPHOBIC & HYDROPHILIC INTERACTIONS HYDROPHOBIC – “WATER-FEARING” NONPOLAR MOLECULES NO AFFINITY FOR WATER HYDROPHILIC – “WATER-LOVING” POLAR MOLECULES HAVE AN AFFINITY FOR WATER

8. VAN DER WAALS INTERACTIONS WEAK INTERACTIONS BETWEEN MOLECULES OR PARTS OF MOLECULES THAT RESULT FROM TRANSIENT LOCAL PARTIAL CHARGES WAIT. WHAT? VIDEO