You are a scientist observing a membrane through which water and some small hydrophobic molecules can freely pass along a concentration gradient from high to low.However,some sugar molecules are too large to pass through the membrane either way without the assistance of passive transport proteins.Additionally,small Na⁺ ions and some proteins can pass through the membrane against the concentration gradient,but both require the assistance of active transport proteins.What general type of membrane are you observing?

Question

Quizplus · Accepted Answer

A semipermeable membrane allows certain molecules or ions to pass through while others cannot. This matches the observation of the membrane in the scenario, where water and small hydrophobic molecules can pass freely but sugar molecules cannot. Additionally, the fact that some molecules can pass against the concentration gradient with the assistance of active transport proteins also suggests that the membrane is semipermeable.

You Are a Scientist Observing a Membrane Through Which Water