Photographic reconstruction of the zone corresponding to the central nerve of the leaf observed with the objective of 40x. The image shows the projection of the central nerve throughout the limb. The most external part corresponds to the lower epidermis, whose cells are provided with a red-stained cuticle. Below it are located the collenchyma (typical of this zone of the leaf) and the assimilating parenchyma, around the vascular bundle. This last element is formed by a part of xylem (located towards the zone of the foliar bundle) and a part of phloem (yellow) underneath. We can also perceive the vascular elements of the xylem, showing the thick red-stained cell walls, radially arranged. The parenchyma of the xylem is located in between, whose elements are also radially arranged, but not red-stained