Answer;
-Large polar molecule are list likely to cross the phospholipid bilayer.
Explanation;
-A large polar molecule would be the least likely to passively diffuse through a plasma membrane without the help of a transport protein. Both its size and the hydrophobic interior of the membrane would restrict it.
-Only small uncharged molecules can diffuse freely through phospholipid bilayers. Small nonpolar molecules, such as O2 and CO2, are soluble in the lipid bilayer and therefore can readily cross cell membranes.
-Ions and large polar molecules cannot pass through the lipid bilayer. But more specifically, whether a molecule can pass through the membrane depends on its size and its electrical nature.
