Class 12th Biology 2013 Set1 Delhi Board Paper Solution
Question 12
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
This response is called allergy. This immune response is produced for a substance called allergen. Allergy is due to release of chemicals like histamine and serotonin from mast cells. The antibodies produced in these are IgE type.
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