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.

Question

Quizplus · Accepted Answer

The blood-brain barrier is a unique feature of the CNS that prevents many chemicals, including drugs and toxins, from passing from the circulatory system into CNS neurons. This barrier is formed by specialized cells that line the walls of blood vessels in the brain and spinal cord, and it helps to protect the delicate neurons of the CNS from potentially harmful substances.

Many Chemicals Are Kept from Passing from the Circulatory System