You are studying the transport of a particular substance into epithelial cells grown in culture. You notice that you can only find the substance inside the cell when ATP is present. How is the protein moving through the membrane?
A)diffusion
B)facilitated diffusion
C)passive transport
D)active transport

Question

Quizplus · Accepted Answer

The fact that the substance can only enter the epithelial cell in the presence of ATP indicates that the transport mechanism requires energy expenditure. Therefore, the protein is likely moving through the membrane via active transport.

You Are Studying the Transport of a Particular Substance into Epithelial