Detailed Instructions: In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
Problem:Question: One of the following types of transport through membranes does NOT exist:
Options: <1> Ion transport facilitated by ionophore (against electrochemical gradient). <2> Facilitated diffusion (in favor of electrochemical gradient) <3> Primary active transport (against electrochemical gradient). <4> Ionic channel (in favor of electrochemical gradient). <5> Simple diffusion (in favor of concentration gradient).
Solution:
1