Many Chemicals Are Kept from Passing from the Circulatory System

question 33

Multiple Choice

Many chemicals are kept from passing from the circulatory system of the CNS into CNS neurons by

• A) reflexology.
• B) the blood-brain barrier.
• C) tolerance.
• D) the cerebrospinal fluid.
• E) withdrawal.

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Definitions:

Cost-output Elasticity

A measure of the responsiveness of the cost of production to a change in the level of output, indicating how costs change as production scales.

Economies of Scale

Refers to the cost advantage that arises with increased output of a product, where fixed costs are spread out over more units of output.

Economies of Scope

Cost advantages that enterprises obtain due to a broader scope of operations, often through producing a variety of products rather than specializing in just one.

Marginal Products

The extra output obtained by utilizing an additional unit of a specific input while keeping all other inputs unchanged.