Question

A student on a school trip started sneezing and wheezing soon after reaching the hill station for no explained reasons. But on return to the plains, the symptoms disappeared. What is such a response called? How does the body produce it?

Answer 1

This response is called allergy. This immune response is produced for substances called as allergens. In a way, allergy is over-reaction of body's immune system against allergens. Allergy is due to release of chemicals like histamine and serotonin from mast cells. The antibodies produced in these are IgE type.