Which of the Following Are Possible Combinations of Mechanisms for Transport

Multiple Choice

Which of the following are possible combinations of mechanisms for transport of a particle against a concentration gradient across an epithelial cell?

A) Passive diffusion from a lumen into the cell followed by facilitated diffusion from the cell into the blood
B) Passive diffusion on the apical side into the cell followed by primary active transport on the basolateral side
C) Secondary active transport on the mucosal side followed by facilitated diffusion on the serosal side
D) Both passive diffusion from a lumen into the cell followed by facilitated diffusion from the cell into the blood and passive diffusion on the apical side into the cell followed by primary active transport on the basolateral side are correct
E) Both passive diffusion on the apical side into the cell followed by primary active transport on the basolateral side and secondary active transport on the mucosal side followed by facilitated diffusion on the serosal side are correct