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( Nervous system)
The nervous system is a network of specialized cells that communicate information about an animal's surroundings and itself. It processes this information and causes reactions in other parts of the body. It is composed of neurons and other specialized cells called glia, that aid in the function of the neurons. The nervous system is divided broadly into two categories the peripheral nervous system and the central nervous system. Neurons generate and conduct impulses between and within the two systems. The peripheral nervous system is composed of sensory neurons and the neurons that connect them to the nerve cord, spinal cord and brain, which make up the central nervous system. In response to stimuli, sensory neurons generate and propagate signals to the central nervous system which then processes and conducts signals back to the muscles and glands. The neurons of the nervous systems of animals are interconnected in complex arrangements and use electrochemical signals and neurotransmitters to transmit impulses from one neuron to the next. The interaction of the different neurons form neural circuits that regulate an organism's perception of the world and what is going on with its body, thus regulating its behavior. Nervous systems are found in many multicellular animals but differ greatly in complexity between species.[1] The human nervous system can be described both by grass anatomy, (which describes the parts that are large enough to be seen with the naked eye,) and by microanatomy, (which describes the system at a cellular level.) In gross anatomy, the nervous system can be divided into distinct organs, these being stations through which the neural pathways cross. These organs can be divided into two systems the central nervous system (CNS) and the peripheral nervous system (PNS).[2] The central nervous system (CNS) is the largest part of the nervous system, and includes the brain and spinal cord. The spinal cavity holds and protects the spinal cord, while the head contains and protects the brain. The CNS is covered by the meninges, a three layered protective coat. The brain is also protected by the skull, and the spinal cord is also protected by the vertebrae. The PNS is a regional term for the collective nervous structures that do not lie in the CNS. The bodies of the nerve cells lie in the CNS, either in the brain or the spinal cord, and the longer of the cellular processes of these cells, known as axons, extend through the limbs and the flesh of the torso. The large majority the axons which are commonly called nerves, are considered to be PNS.
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Nervous system Subcategories
Nervous system Articles
Is Fish Oil Really Better Than Flaxseed Oil? by Yuri Elkaim
Fish oil or flaxseed oil? That is the question posed by millions of health-conscious people each day. But what is the main reason why millions of people are reaching for either fish oil or flaxseed oil? If you said omega-3 fatty acids then you’re ...
Top 4 Nutrients For Brain Power by Raymond Lee
The key strategy for tuning up the nervous system is to provide your body with the nutrients it needs to make healthy nerve cells, to protect them from damage, and to enhance their ability to carry out their functions. The results can be astounding. ...
Multiple Sclerosis Treatment Methods by Juliet Cohen
Multiple sclerosis is an autoimmune disease and affects the central nervous system. Central nervous system is made up of nerves that act as the body's messenger system. It damages the myelin sheath, the material that surrounds and protects your nerve...
Do You Believe That A Good Tasty Lunch Can Make You Happy? by Yulia Berry
While you are dieting, your brain cells try to save energy and you unintentionally want to avoid any stress, including strong positive emotions, like joy, happiness, ecstasy, etc. If your brain cells do not get optimal nutrition, they grow old and do...
Exercise May Improve Sleep by Dr.Lanny Schaffer
Several million Americans have chronic sleep problems and insomnia. Recent studies show that exercise may improve the quantity and quality of sleep.
Researchers are not sure why exercise may help sleep, but the physical mechanism may be a cha...
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