33Plant Structure TransportMedium1 markWhich statement about the transport of sucrose in plants is correct?AThe hydrogen ion (proton) concentration gradient, on which the transport of sucrose into companion cells depends, is maintained by active transport.BSucrose moves through plasmodesmata by passive diffusion from mesophyll cells into companion cells down the concentration gradient.CATP synthesised by the mitochondria in companion cells provides the energy for the active transport of sucrose from companion cells into phloem sieve tube elements.DWater enters companion cells by active transport causing hydrostatic pressure to build up and push sucrose into phloem sieve tube elements by mass flow.Grade answerGrading criteria