Rhubarb root. Light micrograph of a section through the root of a rhubarb (Rheum sp.) plant. The primary cortex has been shed by the formation of a ci

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Rhubarb root. Light micrograph of a section through the root of a rhubarb (Rheum sp.) plant. The primary cortex has been shed by the formation of a circular meristem, the periderm, which forms an outer cork layer (phellum, red). This root shows anomalous secondary thickening. The cambium tissue contains an outer layer of xylem vessels (red) and inner layer of phloem (dark blue) vessels. The small rays (red) radiating from the centre, is the primary xylem tissue. Magnification: x3 when printed 10 centimetres wide.

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Size: 5126px × 3417px
Photo credit: © DR KEITH WHEELER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: angiosperm, angiosperms, anomalous, background, biological, biology, botanical, botany, cambium, cell, cells, close-, cork, cortex, cut, cut-, cut-outs, cutout, cutouts, cytological, cytology, detail, dicot, dicots, dicotyledon, dicotyledons, histological, histology, layer, layers, light, meristem, micrograph, microscope, microscopy, outs, periderm, phellum, phloem, plant, plants, primary, rheum, rhubarb, root, secondary, section, sectioned, shed, sp., stain, stained, structural, structure, structures, thickening, tissue, vessel, vessels, white, xylem