Download Lipids

Biochemistry
Lipids
Lipids
 Commonly known as fats.
 Includes oils, waxes, & steroids.
 Contain C,H,O (no 2:1 ratio)
 Hydrophobic (water fearing molecules)
 Main functions
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Long term storage of energy
Insulation
Protection
Form membranes
Hormones (steroids)
Types of Lipids
 Neutral fats/Triglycerides Fats, waxes and
oils
 Phospholipids – Make cell membranes
 Steroids (Sterols) - serve as structural
elements in cell membranes, vitamins, & as
hormones.
Triglycerides
“Fats”
3 fatty acids and a glycerol molecule.
Waxes, oils and “fats”
Involved in long term energy storage, insulation and
protection (cushioning to vital organs or protective
layers – ex. wax on leaves of plants)
Saturated vs Unsaturated Fat
Saturated fat
• All three fatty acid chains contain
the maximum number of
hydrogen atoms (NO DOUBLE
BONDS BETWEEN THE
CARBON ATOMS)
• Mostly animal fats (Lard and
Butter)
• Solid at room temperature
Unsaturated fat
•At LEAST ONE fatty acid chain
does not contain the maximum
number of hydrogen atoms (HAS
AT LEAST ONE DOUBLE BOND
BETWEEN THE CARBON
ATOMS) (Mono—only one double
bond and poly—two or more
double bonds)
•Mostly plant and fish fats
•Liquid at room temperature
Foods high in Fats
 Butter
 Processed meats like sausage and salami
 Avocado
 Nuts
NOT ALL FATS ARE UNHEALTHY – UNSATURATED
FATS IN OILS, FISH, NUTS AND VEGETABLES ARE
VERY HEALTHY FOR YOU (Omega- 3 Fatty Acids)
TRANS FATS ARE VERY UNHEALTHY!!!! Have been
linked to cancer and heart disease.
Phospholipids
• Complex lipids which include a phosphate
group
• Formation of cellular membranes
Steroids...
 Sterols consist of 4 carbon
rings joined to one another.
 Chemical signals
(Hormones)
 Structure (Cholesterol)
 Examples: sex hormones,
cortisone, & cholesterol.
 Lipid structural models
Test for lipids
Paper test
Paper will become dark and “Waxy”
in the presence of fat
Sudan IV Test
Red satin that turns fat red