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Home punjab-curriculum-and-textbook-board-pctb 10th-class biology Biology 10 IMMUNITY9.5 ALLERGIES

Topic 9.52 mins readmedium Level2024 Edition

9.5 ALLERGIES

An allergy is an overreaction of the immune system to a harmless substance, known as an allergen. When an allergen enters the body, the immune system mistakenly identifies it as harmful and attempts to fight it off, leading to an allergic reaction. Common causes of allergies include:

Allergens can be:

Symptoms of allergic reactions vary depending on the individual and the allergen, but may include:

Topic Tags:#allergies#allergens#anaphylaxis#inhalation allergies#ingestion allergies#skin contact allergies#injection allergies

9.4 VACCINES EXERCISE - IMMUNITY