Allison Has Severe Hay Fever

question 6

Multiple Choice

Allison has severe hay fever. What is the mechanism for her hypersensitivity?

• A) IgE antibodies bound to mast cells bind an allergen. Histamine and other mediators are released, causing symptoms.
• B) Allergens combine with antibodies, forming complexes that deposit in tissue and cause tissue damage.
• C) T cells become activated after repeated exposure to an allergen. Chemical mediators are released about 24 hours later, resulting in inflammation of the skin.
• D) Autoantibodies attack "self" cells and tissues, resulting in inflammation and tissue damage.

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Definitions:

Perfect Competition

A market setup where numerous buyers and sellers interact, offering identical products, with no barriers to entry or exit, and complete transparency of information, resulting in suppliers having no control over prices.

Monopoly

A market structure characterized by a single seller, selling a unique product in the market. This seller faces no competition, as he is the sole seller of goods with no close substitute.

Output

refers to the total amount of goods or services produced by a firm, industry, or economy within a certain period.

Profit-Maximizing Rule

A principle stating that profit maximization occurs when a firm expands output until marginal cost is equal to marginal revenue.