Tag: bio-chemistry

Fatty acids are of two types, the saturated fatty acids that have single bond across the carbon chain and the unsaturated fatty acids that have one or more double bond across the carbon chain. When there are more than one double bonds, they are called the polyunsaturated fatty acids. These are called the essential fatty acids as they cannot be synthesized in the body and must be supplied through the external source. Linoleic acid and linolenic acid are the essential fatty acids.

An unsaturated fat is a fat or fatty acid in which there is one or more double bond in the fatty acid chain. A fat molecule is monounsaturated if it contains one double bond, and polyunsaturated if it contains more than one double bond. Where double bonds are formed, hydrogen atoms are eliminated.

Arachidonic acid is not one of the essential fatty acids. Rather it is conditionally essential fatty acid which, becomes essential if its precursor, linoleic acid is deficient thereby resulting in the inability to convert linoleic acid to arachidonic acid. However, some mammals lack the ability or have a very limited capacity to convert linoleic acid to arachidonic acid, making it an essential part of their diets. So, the correct answer is 'Arachidonic acid'.

Essential fatty acids are those compounds which cannot be synthesized by human and must be ingested externally. Examples of essential fatty acid include linoleic (omega-6 fatty acid) and alpha-linolenic acid (omega-3 fatty acid). Linoleic acid is converted to arachidonic acid. Arachidonic acid is an omega-6 unsaturated fatty acid required by proper functioning of body. 

Fatty acids are long, straight chain carboxylic acids. A fat (or oil) is formed when three fatty acid molecules react with a glycerol molecule to yield a triglyceride. Fats in the body are transported and stored as triglycerides.