Lipids
Properties
Are a heterogeneous group of compounds, mainly composed
of hydrocarbon chains.
Are energy-rich organic molecules, which provide energy for
different life processes.
In biological systems because they form the cell membrane,
a mechanical barrier that divides a cell from the external
environment.
Pure fats and oils are colorless, odorless, and tasteless.
They are energy-rich organic molecules
Insoluble in water
Soluble in organic solvents like alcohol, chloroform, acetone,
benzene, etc.
Classification
Saponifiable
Nonsaponifiable
A nonsaponifiable lipid cannot be broken up into smaller
molecules by hydrolysis, which includes triglycerides, waxes,
phospholipids, and sphingolipids.
A saponifiable lipid contains one or more ester groups allowing it
to undergo hydrolysis in the presence of an acid, base, or
enzymes.
Types
Simple lipids
Complex Lipids
Fats: Esters of fatty acids with glycerol. Oils are fats in the liquid
state.
Waxes: Esters of fatty acids with higher molecular weight
monohydric alcohols
Phospholipids: Lipids containing, in addition to fatty acids and
alcohol, a phosphoric acid residue.
Glycolipids (glycosphingolipids): Lipids containing a fatty acid,
sphingosine, and carbohydrate.
Derivated Lipids
Hydrolysis product of simple and compound lipids is called
derived lipids. They include fatty acid, glycerol, sphingosine and
steroid derivatives.
Steroid derivatives are phenanthrene structures that are quite
different from lipids made up of fatty acids. Biological Functions
Energy Storage
Insulation
Acts as hormones
Activator of enzmes
What are Lipids?
These organic compounds are nonpolar molecules, which
are soluble only in nonpolar solvents and insoluble in water
because water is polar molecules.
