Which of the following is a principle of the fluid mosaic model of cell membrane structure?
A) All proteins associated with the cell membrane are contained in a fluid layer on the outside of the cell.
B) The lipid bilayer is a solid at body temperature, thus protecting the cell.
C) Phospholipids consist of a polar head and a nonpolar tail made of three fatty acid chains.
D) Phospholipids form a bilayer that is largely impermeable to water-soluble molecules.

Question

Quizplus · Accepted Answer

The principle of the fluid mosaic model of cell membrane structure is that the membrane is composed of a phospholipid bilayer that is fluid and allows for the movement of proteins within it. The bilayer is largely impermeable to water-soluble molecules, which is necessary for maintaining cellular integrity and regulating the movement of molecules in and out of the cell. Option A is incorrect because proteins can be embedded within the bilayer, not just in a fluid layer on the outside. Option B is incorrect because the lipid bilayer is fluid at body temperature, not solid. Option C is incorrect because phospholipids have a polar head and a nonpolar tail made of two fatty acid chains, not three.

Which of the Following Is a Principle of the Fluid