This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Physiology
Facilitated diffusion is characterized by all except 
Select and explain. 
A. Vmax, B. Competitive inhibition, C. Requires energy, D. Specificity
C: Requires energy
Answer: C: Requires energy 
Explanation: This process is called passive transpo orfacilitated diffusion, and does not require energy. The solute can move "uphill," from regions of lower to higher concentration. This process is called active transpo, and requiressome form of chemical energy. Ref ganong's review of medical physiology 25e p102