PATHOLOGY

Detailed explanation-1: -The blood that nourishes the brain and spinal cord is behind the glial-cell–enforced blood-brain barrier, which limits the exchange of material from blood vessels with the interstitial fluid of the nervous tissue. Thus, metabolic wastes are collected in cerebrospinal fluid that circulates through the CNS.

Detailed explanation-2: -Recent findings: Dr. Armour, in 1991, discovered that the heart has its “little brain” or “intrinsic cardiac nervous system.” This “heart brain” is composed of approximately 40, 000 neurons that are alike neurons in the brain, meaning that the heart has its own nervous system.