Which description of facilitated diffusion is correct?
Answer and explanation
Correct answer: A. Passive movement of polar molecules through channel or carrier proteins
- Step 1: It needs no ATP and moves down a concentration gradient. Step 2. Charged and polar molecules cannot cross the lipid bilayer directly, so proteins assist. Answer: Passive movement of polar molecules through channel or carrier proteins. Why not the others: that describes active transport; water movement is osmosis; vesicle uptake is endocytosis.
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