Why is it so difficult for many toxins and poisons to penetrate the blood-brain barrier?
A) Because the human immune system has killer t-cells that attack such foreign agents.
B) Because those agents are too large to get out of the human blood stream.
C) Because the presence of such invaders triggers a fever, which kills them.
D) Because those agents are not soluble in fat.

Question

Quizplus · Accepted Answer

The blood-brain barrier is made up of cells that are tightly joined together, creating a barrier that only allows certain substances to pass through. Many toxins and poisons are not soluble in fat, which is a characteristic required to cross the blood-brain barrier. This is why it is difficult for them to penetrate the barrier and affect the brain.

Why Is It So Difficult for Many Toxins and Poisons