Tight Junctions Between Capillary Endothelial Cells in the Central Nervous

question 39

Multiple Choice

Tight junctions between capillary endothelial cells in the central nervous system create the blood -brain barrier, thereby restricting what type of movement of molecules into the brain?

• A) diffusion of lipophilic
• B) transcytosis of
• C) diffusion of hydrophilic
• D) facilitated diffusion of hydrophobic
• E) active transport of

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Definitions:

Average Total Cost

The total cost of production divided by the quantity of output produced, representing the cost per unit of production.

Economies of Scale

Cost advantages obtained by an increase in production, leading to a reduction in average costs per unit.

Long-run Average Total Cost

The average total cost of production when all inputs, including capital, are variable, typically illustrating economies of scale.

Marginal Cost

The increased cost resulting from the creation of one more unit of a good or service.