IN THIS NOTES WE WELL LEARN ABOUT LIPIDS LIPIDS CHARACTERS DIFFERENCE BETWEEN OIL &FAT SATUATED AND UNSATURAED TRIGLYCERIDES GLYCEROL STRUTRUE OF LIPIDS TYPES CLASSFICATION OF LIPIDS

1. 1
LIPIDS;
DEFINITION;
 These organic compounds are non-polar molecules, which are soluble only in
non-polar solvents and insoluble in water
BLOOR CRITERIA;
 They Must Be Insoluble In Water.
 Soluble In Organic Solvent.
E.g ether,chloroform etc
 Can’t be utilized by living organisms.
 They ester of alcohols.
TYPES OF LIPDS;
1. Triglycerides
2. Phospholipds
3. Steroids
4. Waxes
FATS;
Fat usually means any ester of fatty acids, or a mixture of such compounds
OIL;
Fats that are liquid at room temperature are called oils.
Difference between Fats and Oils
Fats Oils
Solid at room temperature Liquid at room temperature
Saturated and trans are its types
Unsaturated fats like
monounsaturated and

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polyunsaturated are its types
Mostly derived from animal Mostly derived from plants
Increases cholesterol levels Improves cholesterol levels
Mainly comes from animal food but also
through vegetable oil by process called
hydrogenation
Mainly comes from plants or fish
Example: Butter, beef fat Example:Vegetable oil, fish oil
Contains 9 cal/gm Contains 9 cal/gm
FATTY ACID;
DEFINITION:
A fatty acid is a carboxylic acid with an aliphatic chain
TYPES OF FATTY ACID;
i. Saturated fatty acid
ii. Unsaturated fatty acid
I. SATURATED FATTY ACID;
DEFINITION;
The acids that have no double bond (C=C) in their aliphatic chain
are known as Saturated fatty acid

3. 3
II. UNSATURATED FATTY ACID;
DEFINITION ;
The unsaturated fatty acid is a form of fatty acids containing one or
more double bonds
EXAMPLE;
1. TRIGLYCERIDES;
A triglyceride is an ester derived from one glycerol and three fatty acids

4. 4
Waxes;
Definition;
A wax is a simple lipid which is an ester of a long chain alcohol and a
fatty acid.
The alcohol may contain from 12-20 carbon atoms
Example; cetyl alcohol
Cetyl alcohol have 16 carbon atoms
C16 CH12(CH2)14OH
Sources;
i. Bees wax ;(honey comb)
ii. Lanolin; used in cosmetics
iii. Spermacets; used in candles, pharmaceutical preparation

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TYPES;
a. True waxes
b. Non-true waxes
a.True waxes;
Waxes are esters of long chain fatty acids and long chain alcohols
c. Non- true waxes;
Waxes are esters of cholesterol,vitamin D, vitamin A
2. PHOSPHOLIPIDS;
DEFINITION;
These are compound lipids containing phosphoric acid,in addition to
fatty acids nitrogenous base and alcohol
TYPES OF PHOSPHOLIPIDS ;
1. Glycerophospholipds
2. Sphingomyelins
1. GLYCEROPHOSHOLIPIDS;
DEFININTION;
Glycerophospholipds or (phosphoglycerides)that contain glycerol
as the alcohol
They consist of glycerol 3-phosphate
A. Phosphatidic acid;
This is simplest phospholipid.it does not occur in good
concentration in the tissue .basically,phosphatidic acid is an intermediate in the
synthesis of triglycerides and Phospholipds
The other Glycerophospholipds containing different nitrogenous bases or other groups
may be regarded as the derivatives of phosphatidic acid

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B. Lecithin's;(Phosphatidycholine)
These are most abundant group of Phospholipds the cell
membrane .chemically ,lecithin is a phosphatidic with choline as the
base .Phosphatidycholine represent the storage from of body’s choline
C. CEPHALINS(phosphatidylecthanamine);
Ethanolamine is the
nitrogenous base present in cephalins.thus lecithin and cephalin differ
with regard to the base
D. PHOSPHATIDYLSERINE;
The amino acid serine in the group of
Glycerophospholipds.
Phosphatidyltheronine is also found in certain tissues and plays a role in
apoptosis

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E. PLASMALOGENS;
When a fatty acid attached by an ether linkage C1
of glycerol in glycerophospholipids,the resultant compound is
plasmogen.
Sphingomyelins;
Sphingosine is an amino alcohol present in sphingomyelins
(sphingophospholipids).they do not contain glycerol at all.sphingosine is attached by
an amide linkage to a fatty acid to produce ceramide
It is a type of sphingolipid found in animal cell membranes,
especially in the membranous myelin sheath that surrounds some nerve cell axons. It
usually consists of phosphocholine and ceramide, or a phosphoethanolamine head
group

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Ceramide;
As a second messenger (signaling molecule) by regulating
programmed cell death,cell cycle and cell differentiation