which of the following best describes how high levels of cholesterol affect the cell membrane at certain temperatures?

High levels of cholesterol make the cell membrane less fluid at high temperatures and more fluid at low temperatures by buffering how much fluidity changes with temperature.

Core idea

• At high temperatures, cholesterol stabilizes and stiffens the membrane, preventing it from becoming too fluid or “melting.”

• At low temperatures, cholesterol disrupts tight packing of phospholipid tails, preventing the membrane from becoming too rigid or freezing.

• Overall, cholesterol reduces the temperature‑dependence of membrane fluidity: it acts as a fluidity “buffer” so the membrane stays in a useful, semi‑fluid state across a wider temperature range.

So, among typical answer choices, the best description is usually:

“Cholesterol decreases membrane fluidity at high temperatures and increases membrane fluidity at low temperatures, helping maintain relatively constant fluidity over a range of temperatures.”