To form the blood-brain barrier, capillary epithelial cells are sealed together by ____.
A) fibronectin
B) collagen
C) gray matter
D) myelin
E) tight junctions

Question

Quizplus · Accepted Answer

The blood-brain barrier is formed by capillary endothelial cells (not epithelial cells as mentioned in the question) that are sealed together by tight junctions. These tight junctions restrict the passage of substances from the bloodstream into the brain, thereby protecting the brain from toxins and pathogens.

To Form the Blood-Brain Barrier, Capillary Epithelial Cells Are Sealed