Compounds that contain carbon Naturally occurring organic compounds are found in plants, animals, and fossil fuels All of these have a plant origin There are many synthetic organic compounds, but are made from fossil fuels Biologically important organic chemicals are produced by living cells.

1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic Acids

 4 valence electrons  forms covalent bonds  attaches to other carbons to form backbones of biological molecules, which can be:  straight chain  branched chain  ring

 are molecules made up of carbon and hydrogen only.  Even though their carbon-hydrogen bond is polar their molecular shape tends to make them nonpolar.

 A functional group is a reactive cluster of atoms attached to the carbon backbone of organic molecules.  These groups impart certain chemical properties to biological molecules.  They are more reactive than the hydrocarbon backbone.  We will study 6 functional groups (Table 1 on page 25 )

 Represented as -OH  Found in alcohols Examples: Isopropyl alcohol and butyl alcohol

 Represented as -COOH  Found in acids Examples: Vinegar

 Represented as - NH2  Found in bases Examples: Ammonia Amino Acid

 Represented as - SH  Found in rubber Example: Rubber

 Represented as - PO4  Found in ATP Example: Adenosine triphosphate

Represented as - COH  Called an ALDEHYDE when found at the end of a molecule Represented as - CO-  Called a KETONE when found in the middle of the molecule