Lipids
SAMANTHA REESE
DANIELLE NEW
CHANPISEY PHY
What are Lipids?
 Oils
 Fats
 Fatty Acid
 Triglycerides
 Phospholipids
 Steroids ( including cholesterol)
Examples of lipids:
 Lard
 Vegetable oil
 Phospholipids
 Steroids
What is a lipid composed of?
 Fatty acids:
 long carbon skeleton
 usually 16 or 18 carbon atoms in length.
 Fatty acids make lipids hydrophobic
Fats contain glycerol &
Fatty Acids
1
2
3
Fatty Acids:
 Saturated fatty acids Unsaturated fatty acids
Fats are glycerol & Fatty
Acids
Fatty Acids:
 Saturated fatty acids Unsaturated fatty acids
Saturated Fatty Acids
 If there are no double bonds between carbon
 atoms composing the chain, then as many




hydrogen atoms as
possible are bonded to the carbon skeleton.
Such a structure is
described as being saturated with hydrogen,
so the resulting
fatty acid is called a saturated fatty acid.
Most animal fats are saturated:
Unsaturated Fatty Acids
(Cis-Fats)









unsaturated fatty acid has one or more double bonds, formed
by the removal of hydrogen atoms from the carbon skeleton.
The fatty acid will have a kink in its hydrocarbon chain wherever
a cis double bond occurs.
fats of
plants and fishes are generally unsaturated, meaning that they
are built of one or more types of unsaturated fatty acids. Usually
liquid at room temperature, plant and fish fats are referred
to as oils-olive oil and cod liver oil are examples.
Trans Fat
 process of hydrogenating vegetable oils
 produces not only saturated fats but also
unsaturated fats with trans double bonds.
What are the Components of
Phospholipids?
Phospholipids
Bilayer
Source: Biology Campbell 8 ed.
Phospholipids (Cont.)
Many Hormones are Lipids
 Cholesterol is a lipid with a carbon skeleton
with four fused rings
 Cholesterol is the source of hormones that
plays important role in biological endocrine
system
 Eg. Estrogen, Testosterone, Aldosterone
Lipids as Major Membrane Component
 Cholesterol is one of major component of
animal cell membranes.
 the precursor from which other steroids are
synthesized.