A screening showed her to be allergic to a host of allergens, principally grasses, weeds, trees, mold, mildew and dust. Campbell eliminated as much contact as possible with those sneeze-inducers and now takes allergy shots every two weeks. I don't have that in May where I itch so bad. Anatomy of a sniffle We've all seen those hugely magnified photos of ragweed-pollen grains, which resemble giant, prickly golf balls. The actual biological response is a little more complex.
Most allergic individuals inherit only the capacity to become allergic.
And usually, the mucous membranes along the respiratory and intestinal tracts do a good job of keeping out foreign materials. The body's immune system then manufactures antibodies to fight those particular allergens. And when exposed to those same allergens later on, the immune system stimulates specialized mast cells to produce agents that can counter the invasion. Pollen grains, by the way, are the small male reproductive parts of plants. That's because they produce lighter, more buoyant pollen that's whipped along by the wind.