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 6x4.5cm size | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Burgess, Dr. Jeremy |
Taille de l’image : | 3668 px × 4783 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |