A Substance Moves by Facilitated Diffusion into a Cell

Question

A substance moves by facilitated diffusion into a cell.What is required for its transport?
A)ATP only
B)a pump
C)both ATP and a protein channel
D)either a protein channel or a carrier protein

Accepted Answer

Facilitated diffusion is a type of passive transport in which substances move across the cell membrane with the help of a protein channel or a carrier protein. ATP is not required for facilitated diffusion, and a pump is a type of active transport mechanism, not a facilitative one. Therefore, the correct answer is either a protein channel or a carrier protein, as both can serve as facilitators for the movement of molecules into a cell.