Question

which statement below best identifies this form of cellular transport?
a facilitated diffusion, because energy is not being used as a channel protein allows molecules to move with the concentration gradient.
b active transport, because energy is being used to move molecules against the concentration gradient.
c osmosis, because energy is not being used to move water molecules with the concentration gradient.
d endocytosis, because a vesicle is being formed to bring molecules from outside the cell into the cell.

Explanation:

1. Analyze Option A: Facilitated diffusion uses a channel/carrier protein, moves molecules with the concentration gradient (from higher to lower, as shown: higher on left, lower on right, arrow direction matches), and no energy is used. This matches the diagram.
2. Analyze Option B: Active transport moves against the gradient (needs energy), but the diagram shows movement with the gradient (higher to lower), so B is wrong.
3. Analyze Option C: Osmosis is water movement (no channel protein shown here, the diagram has a channel for solute?), and osmosis is usually through aquaporins or lipid bilayer, but the diagram has a channel protein for a solute-like molecule, so C is wrong.
4. Analyze Option D: Endocytosis uses vesicles to bring large molecules, but the diagram shows a channel protein moving small molecules, so D is wrong.

Answer:

A. Facilitated diffusion, because energy is not being used as a channel protein allows molecules to move with the concentration gradient.