14) 14) Which of the following statements best summarizes the acid growth hypothesis in an actively
growing shoot?
A) Auxins activate aquaporins that increase turgor pressure in the cells.
B) Auxin-activated proton pumps lower the pH of the cell wall, which breaks bonds and makes
the walls more flexible.
C) Auxins and gibberellins together act as a lubricant to help stretch cellulose microfibrils.
D) Auxin stimulates proton pumps in the plasma membrane and tonoplast.