Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
An allergy is an exaggerated or hypersensitive response of the immune system to certain substances in the environment which are normally harmless.
Substances that trigger an allergic reaction are called allergens. Common allergens include dust, pollen, certain foods, and chemicals.
Allergens are classified based on their mode of entry: Inhalants (breathed in, e.g., pollen), Ingestants (swallowed, e.g., nuts, milk), Injectants (bites/stings), and Contactants (skin contact, e.g., latex).
When an allergen enters the body, the immune system produces a specific class of antibodies called Immunoglobulin E, denoted as .
The interaction between the allergen and triggers mast cells to release a chemical called Histamine (), which causes inflammation, itching, and swelling.
Severe allergic reactions can lead to a life-threatening condition called Anaphylaxis, which requires immediate medical attention.
📐Formulae
💡Examples
Problem 1:
A child consumes cow's milk and develops abdominal pain and skin rashes. Identify the type of allergen and the specific protein often responsible.
Solution:
The type is an Ingestant Allergen. The specific proteins responsible are often -lactalbumin or -lactoglobulin found in milk.
Explanation:
Ingestant allergens enter through the digestive tract. The body recognizes the milk protein as a foreign invader and initiates an immune response.
Problem 2:
Explain why a person starts sneezing repeatedly when exposed to flowering plants in springtime.
Solution:
This is due to Inhalant Allergens, specifically pollen grains.
Explanation:
Pollen grains are microscopic particles that enter the respiratory tract. They bind to on the surface of mast cells in the nasal lining, leading to the release of histamine () which causes sneezing and watery eyes.