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Storage Lipids- Fats and Oils
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Universally used as stored form of energy by living organism
Highly reduced compound, derivatives of Fatty Acids
Fatty Acids are hydrocarbon derivatives which are long chain carboxylic acids
containing up to 24 carbon atoms
Most common in plants and animals are even-numbered
Fatty Acids classified as Saturated (All C have single bonds) or Unsaturated
(Contain one or more double bonds)

The fats and oils found in animals and plants are triglycerides
Triglycerides are:
– esters of fatty acids and glycerols
– simple lipids
– important as the storage form of fat in the human body

Waxes
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Apart of lipid family
Esters of long-chain saturated and unsaturated fatty acids
Low melting, stable solids
Both in animals and plants
Wax coat protects surface of plant leaves from water loss and attack from
microorganisms
Waxes coat skin, hairs and feathers and help keep them pliable and waterproof

Membrane Lipids
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Phospholipids
Glycolipids
Sterols
Amphipathic
Hydrophillic head
Hydrophobic tail

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Phospholipid Bilayers
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Can form circular single layered micelle
Or two layers of Phospholipids can line up together to form a bilayer
Phospholipids with short tails more likely to form micelles
Longer tails → Form Bilayers
Micelles aid in transporting and absorbing complex lipids and fat-soluble
vitamins such a Vitamin A

Glycolipids
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Lipids with carbohydrate component
Act as receptors for extracellular compounds and form part of recognition
system that keeps the immune system from attacking the body’s own cells
and tissues
ABO Antigens are glycolipids

Steroids
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Steroids are a family of lipids found in plants and animal
– A steroid contains four fused carbon ring: 17 carbon atoms make the
structural unit of steroids known as steroid nucleus
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– Cholesterol is a precursor steroid for more complex steroids
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Typical animal cell membrane contains about 60% phospholipids and 25%
cholesterol
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The higher the % of cholesterol, the more rigid the membrane
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Transported by HDL and LDL
Exogeneous cholesterol comes from diet (15%)
Endogenous cholesterol is synthesized by the liver 70 % of cholesterol
associated with cellular components (85%)

What are Lipoproteins and why do we need them?
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Lipoproteins are a handful of different molecules that interact with water
insoluble fat molecules, and transports those fats in the plasma
Different lipoproteins are responsible for the transportation of different fats
Lipoproteins allow fat to be dissolved into the plasma

Hypercholesterolemia
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High cholesterol, major risk for heart disease and stroke

Why is Cholesterol Control Important?
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It is one of the MAJOR RISK FACTORS for heart disease
High cholesterol & other fats in the blood can lead to heart disease & stroke
It causes Atherosclerosis
Special cells catch LDL and deposits the cholesterol out of it in the walls of
the blood vessels
HDL usually collects the bad cholesterol and takes it back to liver

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How is high cholesterol detected?
There are two types of Blood tests that determines High Cholesterol:
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Total Cholesterol
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LDL Cholesterol
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This test, which most
doctors use to help determine your risk for problems

Risk Factors of High Cholesterol
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A Family History
Age
Gender
Diet
Cigarette Smoking
Obesity
Medical Conditions: Diabetes, High BP
Stress

Treatment & Care
To reduce cholesterol
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Diet (more plant sources)
Weight loss
Exercise
Medication (such as statins)



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