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A student on a school picnic to a park o...

A student on a school picnic to a park on a windy day started sneezing and having difficulty in breathing on reaching the park. The teacher enquired whether the student was allergic to something.
(a) What is an allergy?
(b) Write the two unique charactristics of the system involved in the response observed in the student.

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(a) Hypersensitivity of body to foreign agents (called allergens) is called allergy.
(b) Sneezing of nose, conjunctivitis of eyes, narrowing of bronchi and difficulty in breathing.
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