Which of the Following Describes the Blood-Brain Barrier

question 47

Multiple Choice

Which of the following describes the blood-brain barrier?

• A) It is fully developed in humans at birth.
• B) It is malleable in order to permit drug compounds into the brain
• C) It cannot be penetrated, even with trauma to the brain
• D) It prevents many drugs from entering the brain

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Definitions:

Positive Economic Profits

Earnings that exceed the total costs, including both the explicit and implicit costs of a business.

Expand

To increase the scale, scope, or size of something, often used in the context of business growth or economic expansion.

Increasing-cost Industry

An industry in which production costs increase as output expands, often due to scarce resources or rising input prices.

Long-run Equilibrium

The condition in which all factors of production can be adjusted, leading to a situation where no firm in the industry wishes to change its output.