Biological functions of Lipids
Lipids are stored in a relatively water - free state in the tissues in contrast to carbohydrates which are heavily hydrated to perform a wide variety of functions.
1. Body lipids are reservoir of potential chemical energy. Lipids can be stored in the body in almost unlimited amount in contrast to carbohydrates. Furthermore, lipids have a high calorific value (9.3 calories per gram) which is twice as great as carbohydrate. Large amount of energy is stored as lipid than as carbohydrates.
2. Lipids which forms the major constituent of biomembranes are responsible for membrane integrity and regulation of membrane permeability.
3. The subcutaneous lipids serve as insulating materials against atmospheric heat and cold and protect internal organs.
4. They serve as a source of fat soluble vitamins (Vitamin A, D, E and K) and essential fatty acids. (Linoleic, Linolenic and Arachidonic acid).
5. Lipids serve as metabolic regulators of steroid hormones and prostaglandins.
6. Lipids present in inner mitochondrial membrane actively participate in electron transport chain.
7. Polyunsaturated fatty acids help in lowering blood cholesterol.
8. Squalamine, a steroid, is an potential antibiotic and antifungal agent.