when living cells of nitella are exposed to an acetate buffer solution until the ph value of the sap is decreased and subsequently placed in a solution of brilliant cresyl blue , the rate of penetration of dye into the vacuole is found to decrease in the majority of cases , and increase in other cases , as compared with the control cells which are transferred to the dye solution directly from tap water .
C0042219
vacuole
C0007634
cells