Question
  1. Which agents cause allergy?
  2. How does the human body respond to allergens?

Answer

  1. The exaggerated or hypersensitive response of the immune system to certain agents in the environment is called allergy and its causing elements are called allergens.
  2. Symptoms of allergic reaction includes sneezing, watery eyes, rashes, running nose, difficulty in breathing, etc. Allergy occurs due to the release of chemicals like histamine and serotonin from the mast cells. Drugs like anti-histamine, adrenaline and steroids quickly reduce the symptoms of allergy.

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