<span>Allergy-
A medical condition that causes someone to become sick after eating, touching, or breathing something.
Allergen
A substance or object that causes allergies.
Hope this helps!!
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According to the biological species concept, organisms belong to the same species if they can interbreed to produce viable, fertile offspring. Species are separated from one another by prezygotic and postzygotic barriers, which prevent mating or the production of viable, fertile offspring.
