Examples of lipids include;
- Fats
- Waxes
- Phospholipids
- Sphingolipids
- Steroids
- Vitamins A,D,E and K
Lipids are one of the class of 4 major macro molecules (organic compounds) of our body.
They are taken from external sources like food and edible oils. Also they are made in the body from excess carbohydrates.
There are many types of lipids and vary in terms of structure, properties and the functions in the body.
They are insoluble in water and hence called hydrophobic.
Examples of Lipids:
Lipids are of two types as
a) Simple lipids
b) Compound lipid.
Simple lipids: These are the ones which is an ester of a fatty acid and an alcohol.They are again of two types as
- Neutral fats (glycerides): They have an ester of fatty acid and glycerol. They tend to accumulate in our body and contribute to weight gain. Ex: all edible oils
- Waxes: These are also esters but have fatty acids linked with non-glycerol alcohol. Ex: Bee wax.
The fats are stored in the body and are used in times of starvation.
Compound lipids: These are the complex lipids with an ester of fatty acid, alcohol and other substances. They are mostly involved in formation of membranes of the body cells. They are of different types like
- Phospholips: Which are par of cell membrane
- Sphingolipids which are part of nerve cell membrane
- Steroids especially the cholesterol which forms the cell membrane.
Fatty acid Structure:
Lipids are made of long chain fatty acids esters of alcohols. They are written with the formula
HOOC-(CH)2-CH3 fatty acids
These fatty acids are obtained from different sources like the plants, animals (meat) and even the minerals.
Fats are used as a part of diet. While few like shark liver oil and Cod liver oil are used as medicine. Others like liquid paraffin is used as drug to relive constipation.