General Biology 1 for STEM students

1. Organic Molecule: Lipids
Prepared by:
MR. KEVIN FRANCIS E. MAGAOAY
Faculty, SHS Biology Department
C h a p t e r 10

2. Learning Objectives:
 Define lipids
 Characterize the subtypes of lipids
 Structure of phospholipid
 Molecular components of lipids

3. Overview:
 Definition of lipids
 Subtypes of lipids (phospholipids, triglycerides
and steroids)

4. Lipids
 Lipids include a divers group of compounds that
are nonpolar in nature.
 Composed of CHON atoms
 Lipids include phospholipid, triglycerides and
steroids

5. Phospholipids
 Are the major constituent
of the plasma membrane
 Selectively permeable
membrane
 Composed of two body
regions: hydrophilic head
and hydrophobic tails

6. Phospholipids
 Composed of a fatty acid tails attached to the
glycerol backbone
 First and second carbon of the glycerol backbone
is occupied by saturated and unsaturated fatty
acid tail respectively
 The third carbon of the glycerol backbone is
occupied by a phosphate group

7. Phospholipids

8. Saturated Fatty Acid
 Lipids that are solid at room
temperature are composed mostly
of saturated fatty acids
 Stearic acid (found in wax and
lard) and butyric acid (found in
butter) are examples of saturated
fatty acids.

9. Unsaturated Fatty Acid
 Lipids that are liquid at room
temperature are composed
mostly of unsaturated fatty acids
 Oleic acid and linoleic acid are
unsaturated fatty acids that are
common in vegetable oils

10. Trans Fats
 Unsaturated fats bend because of the cis
configuration
 Trans configuration results in an unsaturated
fatty acid that is a straight chain like a saturated
fatty acid
 Trans fats are rare in nature. Hydrogenation can
create both saturated and trans fatty acids

11. Trans Fats

12. Triglycerides
 Triglyceride is formed by
the joining of three fatty
acids to a glycerol
backbone in a
dehydration reaction
(synthesis)
 3 molecules of water are
released

13. Steroids

14. Fake Fat
 The molecular formula of
olestra suggest why
olestra is not digested
 Olestra is highly insoluble
 Can cause abdominal
cramps