Question

Semipermeable cell membranes are made of phospholipids that form a bilayer.

What major benefit does this arrangement of the membrane provide to the cell?

Responses

It allows interactions with polar and nonpolar molecules.
It allows interactions with polar and nonpolar molecules.

It allows interactions with nonpolar molecules only.

It allows interactions with nonpolar molecules only.

It allows interactions with polar molecules only.
It allows interactions with polar molecules only.

It prevents any interactions between the inside and outside of the cell.

Answer 1

It allows interactions with polar and nonpolar molecules.

Explanation: Phospholipid bilayers have hydrophilic (polar) heads facing the aqueous inside and outside of the cell and hydrophobic (nonpolar) tails in the interior. That structure lets the membrane interact with water and polar substances at its surfaces while the nonpolar core interacts with (and permits passage of) nonpolar molecules, producing selective (semipermeable) transport.