Pine stem. Light micrograph of a section through a single annual growth ring in the stem of a pine (Pinus sp.) tree, showing large thin-walled trachei

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Pine stem. Light micrograph of a section through a single annual growth ring in the stem of a pine (Pinus sp.) tree, showing large thin-walled tracheid cells (whitish pink) of younger spring wood and smaller thick-walled tracheid cells (bright white) of older autumn wood. The large circular lacuna (resin duct, centre) is lined with parenchyma cells (orange-brown). Magnification: x70 when printed 10 centimetres wide.

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Size: 3417px × 5125px
Photo credit: © DR KEITH WHEELER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: autumn, biological, biology, botanical, botany, canal, cell, cells, close-, cytological, cytology, detail, duct, growing, growth, gymnosperm, gymnosperms, histological, histology, lacuna, light, micrograph, microscope, microscopy, older, parenchyma, pine, pinus, plant, plants, resin, ring, section, sectioned, sp., spring, stain, stained, stem, structural, structure, structures, thick-walled, thin-walled, tissue, tracheid, tracheids, tree, trunk, wood, young, younger