Elm stem. Light micrograph of a transverse section through the one-year-old woody stem of an elm (Ulmus procera) tree. The outer layer (epidermis, dar

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Elm stem. Light micrograph of a transverse section through the one-year-old woody stem of an elm (Ulmus procera) tree. The outer layer (epidermis, dark ring) is being sloughed (pushed/broken) off by developing underlying cork (red-brown), underneath which is the cortex made of collenchyma (orange-red). The lower cortex has bands of phloem fibres (red) and a layer of phloem sieve tubes (solid red with cavities). Under the phloem is a ring of cambium (light-red circle) and under this is a thick layer of wood (xylem, purple-red) with six vascular bundles. The solid pith (pink, centre) is composed of parenchyma cells. Magnification: x46 when printed 10 centimetres wide.

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Size: 5362px × 5241px
Photo credit: © DR KEITH WHEELER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -year-, angiosperm, angiosperms, background, biological, biology, botanical, botany, cambium, cell, cells, collenchyma, cork, cortex, cytology, elm, fibre, fibres, flora, light, lm, micrograph, microscope, nature, parenchyma, phloem, pith, plant, primary, procera, rings, section, sectioned, sieve, stem, structure, support, supportive, tracheid, tracheids, tree, tubes, ulmus, vessel, vessels, white, xylem