A substance does not move down a concentration gradient through
A)a symporter
B)an antiporter
C)a primary active transporter
D)a secondary active transporter
E)facilitated diffusion carrier

Question

Quizplus · Accepted Answer

Primary active transporters require energy in the form of ATP to move substances against their concentration gradient. The other options mentioned all involve some form of passive transport, where the substance is moving down its concentration gradient.

A Substance Does Not Move Down a Concentration Gradient Through