Which of the Following Substances Requires Mediated Transport to Cross

Question

Which of the following substances requires mediated transport to cross the blood -brain barrier?
A) hydrogen ions
B) oxygen
C) ethanol
D) carbon dioxide
E) glucose

Accepted Answer

Glucose requires mediated transport to cross the blood-brain barrier, as it cannot pass through the barrier via simple diffusion due to its size and polarity. Specialized transport proteins facilitate its movement into the brain.