school House Rock presents your nervous system
Function of the Nervous system
As shown in the video above the Nervous System sends message to and from the brain to different parts of your body to let it know what it needs or needs to do, through and intricate system of nerves and nerve impulses. These impulses are electrical messages sent from nerve endings through nerve cells to the brain, sensory nerves, or from the brain to lets say your arm through neurons to nerve cells to nerve endings, motor response. All nerve cells can be categorized as either afferent (sensory) or efferent (motor).
Efferent cells are the body's response cells and they work hand in hand with afferent cells. When the afferent cells are stimulated from an outside source, using the videos example, like a fly buzzing around your ear. The brain would send a message, using efferent cells, to your arm to swat the fly away. This would be an example of an efferent voluntary responses. The body also has efferent involuntary responses, this would be like an increase in your heart before your game begins. Efferent involuntary responses are initiated by autonomic cells, whereas efferent voluntary responses are initiated by somatic cells.
Afferent cells are the body's sensory cells. These cells send messages from nerve endings back to the brain. Sensory cells are divided into two categories somatic or visceral. Visceral cells send messages from the organs to the brain, for example hunger is caused by a message sent from your stomach to your brain saying it is time to eat. Somatic cells are the nerve endings found under the skin around the body that stimulated by the environment, for example your skin and your eyes.
Efferent cells are the body's response cells and they work hand in hand with afferent cells. When the afferent cells are stimulated from an outside source, using the videos example, like a fly buzzing around your ear. The brain would send a message, using efferent cells, to your arm to swat the fly away. This would be an example of an efferent voluntary responses. The body also has efferent involuntary responses, this would be like an increase in your heart before your game begins. Efferent involuntary responses are initiated by autonomic cells, whereas efferent voluntary responses are initiated by somatic cells.
Afferent cells are the body's sensory cells. These cells send messages from nerve endings back to the brain. Sensory cells are divided into two categories somatic or visceral. Visceral cells send messages from the organs to the brain, for example hunger is caused by a message sent from your stomach to your brain saying it is time to eat. Somatic cells are the nerve endings found under the skin around the body that stimulated by the environment, for example your skin and your eyes.
structure of the nervous systemThe Nervous system is divided into two groups the Central Nervous System (CNS) and the Peripheral Nervous System (PNS). The CNS consists of the brain and the spinal cord and the PNS consists of the nerves that extend from the central nervous system. Both systems are supported by neuroglia that serve as protection for all nerve cells.
Neuroglia cells differ between the CNS and the PNS. the CNS neuroglia are:
*myelin helps protect nerve cells from damage as well as help nerve cells conduct nerve impulses and action potential nerve cell Diagram |
Nerve Impulses
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The Brain
The Brain is the one running the show in the nervous system, the illustration to the left shows some of the different parts of the brain and what they do, but if you don't feel like enlarging the picture or going to the website to view it here's a brief overview of the sections of the brain.
The Major Brain Regions:
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