27. Based on the acid growth model of cell expansion in the plant, whichstatement is correct?
(A) Proton pumps on the plasma membrane are activated by de novosynthesis of gibberellins.
(B) Protons are pumped from cell wall space into the cytoplasm to acidifythe cell.
(C) Expansins function to re-connect the linkage between cellulosemicrofibrils after cell expansion.
(D) The direction of elongation is perpendicular to the alignment ofmicrofibrils.
(E) The losing reaction of microfibrils can also be observed in the secondarycell wall.