could you tell the activities of the former mentioned organ in the nerve system mentioned above?
Brains exert centralized control over a body's other organs. They act on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones.
Brain
brains exert centralized control over a body's other organs. They act on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones. 
what part of the brain controls cranial nerves Central nervous system how are these nerves named? With Roman numerals I–XII what is the system you mentioned above? It is the part of the nervous system consisting primarily of the brain and spinal cord. can you explain this cord? The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column. what are its divisions? Six to eight motor nerve rootlets branch out of right and left ventro lateral sulci in a very orderly manner. when was the above mentioned number system introduced? From the 14th century what is its origin? It originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. how does this system denote a number that does not have value? "nulla"
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Brain [SEP] Introduction
Physiologically, brains exert centralized control over a body's other organs. They act on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones. This centralized control allows rapid and coordinated responses to changes in the environment. Some basic types of responsiveness such as reflexes can be mediated by the spinal cord or peripheral ganglia, but sophisticated purposeful control of behavior based on complex sensory input requires the information integrating capabilities of a centralized brain. The operations of individual brain cells are now understood in considerable detail but the way they cooperate in ensembles of millions is yet to be solved.