Chapter 4: Carbon and the Molecular Diversity of Life

1
Chapter 4 Carbon and the Molecular Diversity of
Life
2
I. Organic Chemistry

• Branch of chemistry focusing on carbon compounds
• Berzelius first to distinguish between organic
  (from living) and inorganic (from non-living)
  compounds
• Wohler made urea from inorganic compounds
• Miller made organic compounds from early
  Earth-like atmosphere

3
(No Transcript)
4
II. Versatility of Carbon

• Does not form ionic bonds very often
• Tetravalent - makes four covalent bonds
• Can make large, complex molecules
• Carbon is very compatible with other elements
• CO2 is the source of all carbon in organisms

5
(No Transcript)
6
III. Changes in the Carbon Skeleton

• Hydrocarbons - only hydrogen and carbon
• Isomers - same molecular formula, different
  structures
• Structural Isomers, Geometric Isomers, and
  Enantiomers

7
(No Transcript)
8
(No Transcript)
9
IV. Functional Groups

• Regions of organic molecules most commonly
  involved in chemical reactions

10
A. Hydroxyl Group

• -OH
• Alcohol - organic compound containing an hydroxyl
  group (ethanol)
• Polar because of electronegative oxygen

11
B. Carbonyl Group

• -CO oxygen atom joined to a carbon atom through
  a double bond
• Aldehyde - carbonyl group is at the end of the
  carbon skeleton (propanal)
• Ketone - carbonyl group anywhere else (acetone)

12
Formaldehyde and Acetone
13
C. Carboxyl Group

• -COOH oxygen atom is double-bonded to a carbon
  atom that is also bonded to a hydroxyl group
• Carboxylic (organic) acids
• Formic acid and acetic acid

14
D. Amino Group

• -NH2 (-NH3-)
• Amines
• Amino Acids

15
E. Sulfhydryl Group

• -SH
• Resembles a hydroxyl group. WHY?
• Thiols
• Found in Cysteine

16
F. Phosphate Group

• -PO42- phosphate ion covalently attached by one
  of its oxygen atoms to the carbon skeleton
• Nucleic acids