PSY290H5 Chapter Notes - Chapter 3: Scanning Electron Microscope, Ventricular System, Electron Microscope
Document Summary
Protecting the cns is cerebrospinal fluid (csf), which fills the subarachnoid space, central canal of the spinal cord, and the cerebral ventricles. These three areas are connected by a series of openings that form a single reservoir. Cerebral aqueduct: connects the third and fourth ventricles. Occasionally the flow of the csf is blocked by a tumor near one of the narrow channels that link the ventricles. The buildup from a blockage causes the walls of the ventricles (and the entire brain) to expand producing a condition known as hydrocephalus (water head) and must be treated by draining the excess fluid. Blood-brain barrier (bbb): a mechanism that impedes the passage of many toxic substances from the blood into the brain. The cells that form this blood vessel are tightly pack, forming a barrier to the passage of many molecules, especially large ones and proteins.
