A scientist is 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 they observing?

Question

Quizplus · Accepted Answer

The membrane being observed is semipermeable, meaning that it allows some molecules to freely pass through while others require assistance. This is demonstrated by the fact that water and small hydrophobic molecules can pass through along a concentration gradient, but larger molecules like sugars cannot. Additionally, some molecules like small Na⁺ ions and proteins can pass through but require the assistance of active transport proteins.

A Scientist Is Observing a Membrane Through Which Water and Some