Essay on Nervous System

Submitted By solemly
Words: 1802
Pages: 8

Nervous system

Moving, breathing, the ability to physically feel; one may wonder how. How are all these things, these simplified actions, possible? The answer that is giving is simplistic in nature and yet is so complex in actuality. The simplistic answer is the Nervous system. The Nervous system, however, is never simple: the organs, the location (while it may be simple in theory the things that could happen because of it are not), the amount of time dedicated to learning to help people with something wrong involving it, the diseases, the procedures and even the words; are not simple, and they most likely never will be. There are several overall significant organs within the nervous system and they are all very important. One of these significant organs are the cranial nerves. There are twelve cranial, or at least twelve main ones. One: the olfactory nerve—a purely sensory nerve—transmits the sense of small and allows it to be processed within the brain. Two: the optic nerve—another purely sensory nerve—is for transmitting visual information to the brain. Three: the oculomotor nerve—mainly a motor oriented nerve—controls the movement of the eyeball and the eyelid. Four: the trochlear nerve—another mainly motor oriented nerve—turns the eyes downward and laterally. Five: the trigeminal nerve—both a sensory and motor oriented nerve—is responsible for the muscles for chewing and, also, for receiving sensation from the facial area. Six: the abducens nerve—also mainly motor oriented—turns the eyes laterally. Seven: the facial nerve—both a sensory and motor oriented nerve—controls the secretion of tears and saliva and most of the facial movements. Eight: the vestibulocohlear nerve—mostly a sensory nerve—is an auditory nerve that controls hearing and equilibrium sensation. Nine: the glossopharyngeal nerve—both a sensory and motor oriented nerve—receives taste from one-third of the tongue, proves movement for the stylopharyngeus (a muscle that stretches from between the styloid process and the pharynx) and senses the carotid blood pressure. Ten: the vagus nerve—both a sensory and motor oriented nerve—senses aortic blood pressures, slow heart rates, and stimulates digestive organs, it also helps with the sense of taste. Eleven: the accessory never(also referred to as the spinal accessory nerve of the cranial accessory nerve)--a mainly motor oriented nerve—controls trapezius and sternocleidomastoid, muscles and swallowing movements. And finally, twelve: the hypoglossal nerve—another mainly motor oriented nerve—controls the movements of the tongue, therefore allowing speech. Other significant organ within the nervous system are: the spinal nerves, neurons, the brain, the brain stem, and the spinal cord. The spinal nerves rely all impulses, information and sensations from around the entire body—internally and externally—to the brain for processing and so the body can take what action is say fit. Another important organ are the neurons, which allow rapid transition of signals, whether they be electrical or chemical, to other neuron through the synapses or inter-neurons—which are membranes that connect two or more neurons.. Sensory neurons transmute physical stimulation to the CNS, while the motor neurons transmute active muscles and glands or information going out from the CNS. Then there is the brain, the epicenter. The brain is the center of all commands and monitors all conscious and unconscious processes of the body. It coordinates all voluntary and involuntary movements along with organs. There is also the brain-stem, which is located near the base of the skull and connects to the cerebrum with the spinal cord. The brain-stem actually consists of the midbrain, medulla oblongata, and the pons and the whole is used to transmit signals between the brain and the spinal cord. Motor control comes from the signals sent from the brain to the body—which are coordinated by the brain-stem—it also controls autonomic functions that…