3D representation of a segment from the growth zone of a maize leaf. The sample was fixed in acetone and stained with propidium iodide according to Truernit et al., 2008. The optical stack (80µm, n=144, 0.56 µm/slice) was taken with an Olympus FV1000 confocal microscope (60x magnification, n.a.1.2) and the 3D image was reconstituted with the Velocity 3D Image analysis software package (Perkin Elmer).dd