According to the fluid mosaic model of cell membranes, phospholipids ________.
A) can move laterally along the plane of the membrane
B) frequently flip-flop from one side of the membrane to the other
C) occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane
D) have hydrophilic tails in the interior of the membrane

Question

Quizplus · Accepted Answer

The fluid mosaic model proposes that phospholipids are arranged in a bilayer that is fluid and dynamic. Phospholipids can move laterally along the plane of the membrane, which contributes to the fluidity of the membrane.

Answer: B is incorrect because the flip-flop of phospholipids is a rare event and requires the assistance of specific enzymes.

Answer: C is incorrect because the fluid mosaic model proposes that membrane proteins are integrated into the phospholipid bilayer, with some proteins extending through the entire membrane.

Answer: D is incorrect because the hydrophilic (water-loving) heads of phospholipids are in contact with the aqueous environment both inside and outside of the cell, while the hydrophobic (water-fearing) tails are protected within the interior of the membrane.

According to the Fluid Mosaic Model of Cell Membranes, Phospholipids