Question

The properties of lipids are
A. Insoluble in water and solution in fat solvents.
B. High energy content
C. The structural component of cell membranes
D. All of the above

Answer 1

Hint:Lipids are a class of biomolecules that include highly varied substances, namely, cooking oil, butter, ghee, waxes, cholesterol, essential oils, natural rubber, some plant pigments (carotene of carrot, lycopene of tomatoes), menthol, vitamin A, E and K, and eucalyptus oil.

Complete answer:
1. The member of class lipids differ in chemical structure and function but have a few common features.
2. They are nonpolar and therefore, insoluble in water.
3. They dissolve in nonpolar organic solvents, such as ether, chloroform, acetone, and benzene.
4. They disperse in water uniformly as minute droplets forming an emulsion. Generally, the lipids do not polymerize to form macromolecules. However, they may combine with carbohydrates and proteins.
5. Lipids store reserve food materials. The neural fats serve as food reserves in both plants and animals.
6. The neutral fats form a concentrated fuel, producing more than twice as much energy per gram as do the carbohydrates.
7. The neutral fats form an insulating layer under the skin.
8. The neutral fats serve as a shock-absorbing cushion around the eyeballs, kidneys, and gonads.
9. Birds spread oil from a gland on their tail onto the feathers. This makes feathers less likely to become brittle and get wet.
10. Fat yields water on oxidation.

So the correct answer is option D. All of the above

Note: Lipids are esters of fatty acids with various alcohols. They are of two types neutral and true fats. These are esters of fatty acids with glycerol (glycerine). They are also called glycerides. Waxes are the esters of fatty acids with alcohol other than glycerol.