a layer of tightly packed cells that make up the walls of brain capillaries and prevent substances in the blood from diffusing freely into the brain: passage across the cell membranes is determined by solubility in the lipid bilayer or recognition by a transport molecule.
Scientists Find Bacteria Where It Isn’t Supposed to Be: The Brain Amanda Schaffer March 16, 2013
A physiological mechanism that alters the permeability of capillaries in the brain, so that some substances, such as certain drugs, are prevented from entering brain tissue, while other substances are allowed to enter freely.
Note: Oxygen, glucose, and white blood cells are molecules that are able to pass through this barrier. Red blood cells cannot.
a person’s brother by birth. a male person bound to another by ties of great friendship. something usually associated with or thought to exist inseparably from another thing, quality, circumstance, etc.: Humility is often the blood brother of patience. a male established in a close relationship with another male through the performance of a specific […]
blood capillary Historical Examples Physiology Ernest G. Martin
any of the cellular elements of the blood, as white blood cells or red blood cells. noun any of the cells that circulate in the blood See erythrocyte, leucocyte blood cell A red blood cell or white blood cell that is contained in the blood.