Stinging nettle (Urtica dioica) stinging trichome on a leaf, coloured scanning electron micrograph (SEM). The large spike at upper centre is a stingin

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Stinging nettle (Urtica dioica) stinging trichome on a leaf, coloured scanning electron micrograph (SEM). The large spike at upper centre is a stinging trichome. The other, shorter trichomes are non-stinging ones. When brushed against, the stinging trichome breaks off and its tip penetrates the skin, injecting acetylcholine and histamine. These chemicals cause the painful and inflammatory response known as a nettle sting or rash. Magnification: x63 when printed at 10 centimetres high,

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Size: 3650px × 4861px
Photo credit: © PETER BOND, EM CENTRE, UNIVERSITY OF PLYMOUTH/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 1, acetylcholine, biological, biology, botanical, botany, colored, coloured, cross-section, defence, dioica, false-colored, false-coloured, flora, fracture, fractured, freeze, freeze-fracture, freeze-fractured, hairs, histamine, inflammation, inflammatory, leaf, mechanism, nature, nettle, plant, rash, response, section, sectioned, sem, single, sting, stinging, surface, transverse, trichome, trichomes, urtica