7 The carbon atoms found in the long hydrocarbon chains of f

7. The carbon atoms found in the long hydrocarbon chains of fatty acids and phospholipids are sharing _____ electron(s) with each hydrogen atom in a ______ bond. Fill in the

Fill in the

a) 2;covalent

b) 1; covalent

c) 2; polar covalent

d) 1; polar covalent

e) 1; hydrogen

Solution

Choice d.

Explanation: The fatty acids contain carbon atoms in the long chains. The head portion of the fatty acids contain the phospholipids. These phospholipids contain at least one carbon atom which is joined to other carbon atom by a singlec covalent bond and one or two hydrogen atoms with a covalent bond. A carbon can also be attached to an oxygen atom directly with a double bond. The presence of these covalent bonds make it very difficult for the digestive tract to degrade these fatty acids. Importantly, the whole glycerol unit in the polar head of the fatty acid phospholipid structure is polar in nature and the atoms also experience polarity due to distribution of charge. Thus, the carbon and hydrogen atoms are slightly polarized in a covalent bond in phospholipids.