Scanning electron micrograph (SEM) of pollen grains from the common oak flower Quercus robur. Oak trees flower in May/June producing copious quantiies

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Scanning electron micrograph (SEM) of pollen grains from the common oak flower Quercus robur. Oak trees flower in May/June producing copious quantiies of pollen, which is dispersed by the wind. Oak pollen is a major cause of hay fever (medical term Allergic rhinitis and 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. Mag: X1200 (10x8).

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Size: 4784px × 3696px
Photo credit: © DR JEREMY BURGESS/SCIENCE PHOTO LIBRARY. / Alamy / Afripics
License: Licensed
Model Released: No

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