Assertion . Mast cells in human body release excessive amount of inflammatory chemicals which cause allergic reactions.
Reason . Allergens in the environment on reaching human body stimulates mast cells in certain individuals

Options

A. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
B. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
C. If the assertion and reason are false
D. If the assertion is false but reason is true

Answer

A

Explanation

The symptoms of an allergic reaction develop in response to histamine. Mast cells releases a large amount of histamine into the blood stream and it also act as initiator of the inflammatory response which aids the arival of leucocytes at a site of infection. Histamine stimulates capillary dilation, increased capillary permeability, closure of bronchial tubes, mucus secretion, pain and swelling.