Which of the following statements is NOT correct about the phospholipid molecules in the plasma membrane? A. The polar heads face outward. B. The nonpolar tails face inward. C. The polar heads are hydrophobic. D. The nonpolar tails are hydrophobic. E. The phospholipids form a bilayer.

The correct answer is: C. The polar heads are hydrophobic.

Explanation:

A Plasma membrane is composed of a phospho-lipid bilayer. Each phospho-lipid molecule is composed of: A glycerol moiety that is linked by three ester bonds to, One phosphate group, and Two fatty acid molecules (saturated or absence of double bonds between carbon atoms and unsaturated or presence of double bonds between carbon atoms), which possess long hydrocarbon chains. The fatty acid molecules are hydrophobic in nature, so in order to avoid contact with water molecules they face towards the inner side of the lipid bilayer. They lack any charge and so they are also called Non-polar molecules. The phosphate groups are hydrophilic in nature, so in order to establish hydrogen bonds with water molecules they face towards the outer surface of the lipid bilayer. As they possess an overall negative charge they are also called Polar molecules. Hence, among the given options, the option C is incorrect as here the polar heads are said to be hydrophobic.