1. Lipids Classification Properties Function Basic Structure
Thought for today: If someone calls you a “FAT HEAD”,
first compliment them on their biochemical insight,
before you punch them in their fat head”.

2. What is a Lipid?
Any substance that is insoluble in water but
soluble in organic solvents
Does this mean any water insoluble compound?
Yes
What are some examples I would recognize?
Cholesterol….a steroid
Stearic acid….a saturated fatty acid
Oleic acid…an unsaturated fatty acid
Bees wax….a fatty acid ester
Vitamins A,D,E,K…the fat-soluble vitamins
Tripalmitin…a triacylglycerol
Lecithin…a membrane glycerophospholipid

3. Classifications (all lipids)
Simple vs Complex
Charged vs Neutral
Fatty Acids
Saturated vs Unsaturated
Esterified vs Non-esterified
Odd chain vs Even chain

4. Anatomy of a C14 Saturated Fatty acid
Non-Polar
CH3
COO-
CH2
Charged carboxyl
Methyl end group

5. Fatty Acids Rule: A lipid begins when water insolubility begins CH3
COOH
Getting There
Not yet
Whoa!
C12 saturated fatty acid…..Lauric acid
C14 …..Myristic acid
C16…..Palmitic acid
C18…..Stearic acid
C20…..Arachidic

6. Unsaturated Fatty Acid
Rule: Double bonds in fatty acids are always CIS
C=C H
CH2
Rule: Double bonds are always separated
by a -CH2- group 9 10 12 H
C=C
CH2 2 1 11 3
Rule: Double bonds are always numbered 3 apart
Example 9,12 means a double bond on C9 and C12

7. Rule: Cis double bonds put Kinks in fatty acid chains.
Corr: The more the double bonds the greater the bend
Cis D.B.
Cis D.B.
Saturated
1 D.B.
2 D.B.

8. Trans Fatty Acids are to be avoided for health reasons

9. Rule: Double Bonds lower melting point of a fatty acid
Corr: The more double bonds, the lower the melting point
Room Temperature
Melting
Temperature
All Unsaturated
fats are oils at room
temperature 1 2 3 4
D.B.

10. Complex Lipids What are they?
Lipids molecules comprised of more than one
component….the individual components are readily
disassembled by acid or base hydrolysis
Give me some examples
Acylglycerols = fatty acids esterified to glycerol
-O-C-CH2C-R O
Glycerol
Monoacylglycerol H
R-CH2C-O O H
C-OH CH
Diacylglycerol
HO-
-O-C-CH2C-R O H
Triacylglycerol H
(Triglyceride)

11. Triacylglycerol
Saturated
Mono-
Unsaturated

12. MEMBRANE LIPIDS Glycerophospholipids = 2 fatty acids esterified to
glycerol with phosphate and an amine group
HO-CH2CH2NH3+
CH2O CH
CH2-O O- C O -R R- P
Ethanolamine
HO-CH2CH2N(CH3)3 +
Choline
HO-CH2CCOO-
+NH3 H
Phosphatidate OH . HO
Serine
MEMBRANE
LIPIDS
Inositol

13. HO
Cholesterol