False-colour scanning electron micrograph (SEM) of pollen grains clustered to the stigma of the cocksfoot grass, Dactylis glomerata. Cocksfoot pollen,

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False-colour scanning electron micrograph (SEM) of pollen grains clustered to the stigma of the cocksfoot grass, Dactylis glomerata. Cocksfoot pollen, a summer grass pollen dispersed by the wind, is a major cause of hay fever (medical name Allergic rhinitis & pollenosis). Hay fever sufferers produce a sensitising antibody, immunoglobin E (IgE), which attaches to the surface of cells in the nose & eyes. It reacts with inhaled pollen causing the release of chemicals including histamine. Histamine causes the mucous membranes of the nose, eyes & throat to swell & become inflamed, bringing on the symptoms of hay fever. Magnification: x20 at size.

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Size: 3668px × 4783px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: allergic, botany, cocksfoot, dactylis, false-coloured, fever, glomerata, grass, hay, hayfever, nature, plant, plants, pollen, pollinosis, reproduction, reproductive, rhinitis, stigma