PHYSICOCHEMICAL FOUNDATION OF BIOCHEMISTRY

• Three types of chemical bonding

  • Ionic
  • Covalent
  • Metallic
• Metallic Bonding does not exist in chemical systems
• Ionic Bonding


  Important in discussing the properties of solvent and electrical charges
• Lewis Structure


  Uses valence electron-dots following the octet rule; shared electron-dash
• The greater the electronegativity of two participating atoms in a bond

  The more unequal the sharing
• The more electronegative an atom is

  The higher its density
• Polarity of Molecule


  Determined by the polarity of bonds present in the molecule and the overall molecular shape
• Stereoisomerism


  The same molecular formula with different configuration
• Chiral Center


  A carbon atom with four different substituents and is said to be asymmetric
• Chiral Molecule or Enantiomers


  It mirrors images of each other; same attachments of molecule but differ in their spatial orientation
• Diastereomers


  They do not mirror images of each other
• Chemical Reaction


  It happens when at least two molecules are capable of colliding with each other with enough energy to rearrange their compositions
• A chemical reaction will only change

  If the change in free energy is negative
• Exergonic


  The release of energy
• Endergonic


  The uptake of energy
• Equilibrium


  It happens when the rate of forward and backward reactions are equal
• The relative proportion of the reactants and products do not change when at the equilibrium
• Le Chatlier's Principle


  According to this, a reaction at equilibrium if disturbed will move in such way that the chemical equilibrium will be reestablished
• Chemicals that make up living things

  • C
  • H
  • N
  • O
  • P
  • S
• Carbohydrates


  It is the primary source of energy
• Lipids


  It involves energy storage, cell membrane structure and insulators
• Proteins


  It involves biological processes
• Nucleic Acids


  It involves storing and transmitting genetic information