Which of the Following Is the Best Explanation for Why

question 19

Multiple Choice

Which of the following is the best explanation for why cholesterol decreases the permeability of biological membranes?

• A) Cholesterol binds to the outside surface of a membrane, thus blocking the movement of solutes.
• B) Because cholesterol is amphipathic, it forms tiny vesicles that trap solutes.
• C) Because cholesterol is amphipathic, it fits in between the phospholipids and blocks diffusion through the membrane.
• D) Cholesterol has four rings in its structure that can sequester ("trap") solutes.

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Definitions:

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