The Human Nervous System

p 4 THE HUMAN NERVOUS SYSTEM The nervous system is one of the major systems in the human body . It allows the proper coordination of the sensory and motor neurons with the actions or behavior of an individual . The nervous system of the human body is divided into the peripheral nervous system , which is comprised of motor and sensory neurons that are distributed across the entire body , and the central nervous system , which is composed of the brain and the spinal cord . The role of the nervous may be visualized in the

narration about Prince Ashoka and his journey through the jungles of Ceylon . The story starts with the Prince traveling through the jungle hence the Prince 's physiological state involved employment of the parasympathetic nervous system of the peripheral nervous system , as he was smoothly riding his horse . The Prince was then feeling relaxed and at rest , which is evident as the pupils of his eyes are constricted and his heart was beating at a slow and relaxed state . In addition , his blood vessels are dilated and his digestive and genitourinary systems are normally stimulated

As soon as he approaches a clearing and sees an image of a woman at the edge of a pond , Prince Ashoka 's autonomic nervous system , another division of the peripheral nervous system is stimulated . Through the use of his eyes for seeing the image of a woman , the sympathetic division of the autonomic nervous system is activated . This stimulation is mainly due to his surprise to find someone in the jungle and the idea that he is not along in that area . Such stimulation results in an increase in the heart rate of Prince Ashoka , which in turn results in the increase in blood pressure and blood flow through his body . Other physiological responses related to the stimulation of the sympathetic nervous system of the autonomic nervous system involve the sense of excitement in Prince Ashoka . This physiological modification results in the secretion of adrenaline which is then circulated to the rest of the body . Hence , the Prince 's sensory neurons of the peripheral nervous system in involved in his sighting of the lady by the pond . The sensory neurons of the sympathetic nervous system of the peripheral nervous system carried impulses from his optic sensory neurons and relayed the impulse to the central nervous system (CNS

The cervical spinal nerves of the peripheral nervous system were involved in the reaction of Prince Ashoka to the sight of the lady by the pond . Spinal nerve C1 , which is the sub-occipital nerve , was innervated to relay the signal to the base of Ashoka 's skull . In addition , spinal nerves C2 and C3 , which are located at the neck region of Prince Ashoka , also facilitate the transmission of both sensory and motor control . Hence , the Prince might have reacted to the sighting with a stiffening of his neck muscles . This involves the activation of the greater occipital nerve . Also , the lesser occipital nerve is activated and...