Which characteristic of a phospholipid membrane keeps the aqueous environment inside and outside the cell separate?

Question

Responses

Nonpolar tails on the outside of the membrane repel water.
Nonpolar tails on the outside of the membrane repel water.

Nonpolar tails on the inside of the membrane repel water.
Nonpolar tails on the inside of the membrane repel water.

Polar heads on the outside of the membrane repel water.
Polar heads on the outside of the membrane repel water.

Polar tails on the inside of the membrane repel water.

Answer 1

The correct response to the characteristic of a phospholipid membrane that keeps the aqueous environment inside and outside the cell separate is:

Nonpolar tails on the inside of the membrane repel water.

In a phospholipid bilayer, the nonpolar (hydrophobic) tails face inward, away from the water, while the polar (hydrophilic) heads face outward, towards the aqueous environments both outside and inside the cell. This arrangement helps maintain the separation of the aqueous environments from each other.