What is the blood-brain barrier responsible for?

Question

Quizplus · Accepted Answer

The blood-brain barrier is responsible for prohibiting drugs and other molecules from passing from the bloodstream into the brain. While it is not responsible for "guarding" the brain from drowning, it does act as a filter to prevent harmful substances from affecting the brain. It also does not act as a resource for neurotransmitters, as they are already present in the brain and can communicate with other neurons without having to cross the barrier.

What Is the Blood-Brain Barrier Responsible For