1. CHNOPS: The Six Key Elements of Life
Most biological molecules are made from covalent
combinations of these six elements

2. The backbone of the complex molecules needed for life
Of these CARBON is key
The backbone of the complex
molecules needed for life
aka organic molecules

3. C atoms are versatile building blocks
• valence = 4
• oxidation = +/-4
therefore form 4 bonds
therefore
• potential to create large (macro) molecules
• great variety of forms
yields molecule diversity!

4. HYDROCARBONS : C & H atoms exclusively
Non-polar: not water soluble; hydrophobic
Stable: octet rule fufilled via covalent bonding
Methane : CH4
Simplest hydrocarbon formula

5. H-C chains & rings; big and small

6. Shape Matters form affects function
same formula, different shape defines isomers
Ex: C6H14
The molecular formula C6H14 may refer to:
* Dimethylbutane (disambiguation)
o 2,2-Dimethylbutane
o 2,3-Dimethylbutane
* Hexane
* Methylpentane (disambiguation)
o 2-Methylpentane
o 3-Methylpentane

7. Ex: Thalidomide • synthesized in1950’s
• prescribed for morning sickness (pregnancy)
• one isomer caused severe limb defects
(form) (function)

8. Substituting other atoms or groups around
the carbon changes the function as well
Ex: ethane
vs. ethanol
H replaced by an hydroxyl group (–OH)
nonpolar becomes polar
gas becomes liquid

9. Ex: structure of male & female hormones
• identical carbon skeleton
• attachment of different functional groups
• interact with different targets in the body
• creates different effects

10. Organizing all this diversity
• Sort chemicals into families
defined by their
functional groups
which give organic molecules
distinctive properties
So What?
Functional groups affect reactivity
making
hydrocarbons hydrophilic
therefore
increasing solubility in water

11. Functional Groups be able to recognize these! and: COOH NH2 PO4 OH CO
Methyl
CH3
Proteins

12. carboxyl
methyl
amino
methyl
carboxyl

13. MACROMOLECULES Bigger still Organic More complex C, H, O, N atoms
CELLULOSE
polypeptide polysaccharide