Which of the Following Is a Characteristic of the Blood-Brain

question 13

Multiple Choice

Which of the following is a characteristic of the blood-brain barrier?

• A) it is a single-walled physical barrier
• B) gap junctions bind the endothelial cells in the capillary walls together
• C) there are neurally controlled pores in the capillary walls
• D) there are layers of cells including astrocytes that serve as a secondary barrier

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Definitions:

Beneficence

An ethical principle that involves acting in the best interest of others by promoting their well-being.

Double Effect

A principle in ethics that allows actions which have both a positive effect and a harmful side effect, if the action itself is morally good or neutral, the good effect is intended, and the good outweighs the bad.

Perfect Duty

A moral obligation that must always be followed without exception.

Beneficence

The ethical principle of acting to benefit others, promoting their well-being.