Foreign Substance

question 51

Multiple Choice

Foreign substance:

• A) antigene
• B) antigen
• C) antegen

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Definitions:

Blood-Brain Barrier

Permeability barrier controlling the passage of most large-molecular compounds from the blood to the cerebrospinal fluid and brain tissue; consists of capillary endothelium and may include the astrocytes.

Caffeine

A stimulant found in coffee, tea, chocolate, and certain medications that can enhance alertness and reduce feelings of tiredness.

Glucose

A rudimentary sugar that's crucial for energy in life forms and is a piece of many carbohydrate mixtures.

Oxygen

A chemical element vital for aerobic respiration in living organisms; it is critical for energy production in cells.