False colour scanning electron micrograph (SEM) of a pollen grain attached to the stigma of the cocksfoot grass, Dactylis glomerata. Cocksfoot pollen,

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False colour scanning electron micrograph (SEM) of a pollen grain attached 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 suffer- ers produce a sensitising antibody, immunoglobin E (IgE), which attaches to the surface of cells in the nose & eyes. It reacts with inhaled pollen (an allergen) causing the release of various chemic- als including histamine. Histamine causes the muc- ous membranes of the nose, eyes & throat to swell & become inflamed, bringing on the symptoms of hay fever. Magnification: X385 at 35mm size. original is bw print B786/072

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Size: 3368px × 4770px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: allergic, botany, cocksfoot, dactylis, fever, glomerata, grass, hay, hayfever, nature, plant, plants, pollen, reproduction, reproductive, rhinitis, sem, stigma, type