False colour scanning electron micrograph (SEM) of pollen grains from the common oak flower Quercus robur. Oak trees flower in May/June, producing cop

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False colour scanning electron micrograph (SEM) of pollen grains from the common oak flower Quercus robur. Oak trees flower in May/June, producing copious quantities of pollen, which is dispersed by the wind. Oak pollen is a major cause of hay fever (medical term Allergic rhinitis or pollenosis). Sufferers produce an antibody, immunoglobin E (IgE), which attaches to cells in the nose & eyes. It reacts with inhaled pollen causing the release of various chemicals including histamine. Histamine causes the mucous membranes of the nose, eyes & throat to swell & become inflamed, bringing on the hay fever attack. Magnification: X 340 at 35mm size. original is bw print b786/092

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Size: 3543px × 2342px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: allergic, botany, common, fever, hay, hayfever, nature, oak, plant, plants, pollen, quercus, reproduction, reproductive, rhinitis, robur., sem, type