試題詳解

31. Researchers found a large and polar metabolite X is highly enriched in the extracellular matrix and has a low concentration inside cells. New evidence suggests that the metabolite X is transported from the cell to the extracellular matrix. Based on these findings, wbat is the possible transport mechanism?
(A) passive transport
(B) facilitated transport driven by ATP hydrolysis
(C) primary active transport powered by an ion gradient
(D) secondary active transport and the same transporter transports proton into the cell
(E) secondary active transport and the same transporter transports sodium out of the cell