Question

1. label * a b a b nonpolar tails hydrophobic polar head hydrophilic

Explanation:

Phospholipids in cell - membranes have a structure with polar heads and non - polar tails. The polar heads are hydrophilic (water - loving) and face the aqueous environments inside and outside the cell, while the non - polar tails are hydrophobic (water - fearing) and are oriented towards the interior of the lipid bilayer. In the given diagram, A represents the polar head which is hydrophilic, and B represents the non - polar tail which is hydrophobic.

Answer:

A. Polar Head, Hydrophilic
B. Nonpolar Tails, Hydrophobic