Tag: lipids

Arachidonic acid is a carboxylic acid which has 20 carbon and four double bonds in the cis configuration. It is a polyunsaturated fatty acid (PUFA). It is mainly present in the membrane phospholipids and in platelets. It is also found in liver, erythrocytes, skeletal muscle, cardiac muscle. Meat, egg, and fish are rich sources of arachidonic acid.

Essential fatty acids are those fatty acids that body cannot produce on its own and therefore must be supplied from the diet. Two primary essential fatty acids are linoleic acid and alpha-linoleic acid. Linoleic acid (omega-6) occurs in plant oils like corn oil, palm oil, soybean oil, sunflower oil. Alpha-linoleic acid (omega-3) occurs in fowl and fish like salmon, sardines, tuna.

Unsaturated fatty acid is those which contain one or more double bond in their fatty acids. Generally, it is found in plants fats. It also lowers blood cholesterol. Linoleic is unsaturated fatty acid containing two double bonds. Sunflower oil contains highest linoleic acid. Thus, the correct answer is A.

Fat is stored reserve for the body which provides energy. These are triesters of glycerol. It is obtained from fatty acids and glycerol. It consists of one glycerol molecule and three fatty acid molecules. The carboxyl end of the fatty acid combines with the three -OH groups of the glycerol to form the ester. So, the correct answer is option B.

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.