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Nerve cell (neuron)


Nerve cell (neuron)
The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord.




 


	    Nerve cell (neuron)
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	    Nerve cell (neuron)
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Nerve cell (neuron)


Nerve cell (neuron)
The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord.



 




Close



Nerve cell (neuron)


Nerve cell (neuron)
The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord.


 



Close



Nerve cell (neuron)


Nerve cell (neuron)
The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord.

 

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Nerve cell (neuron)
The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord.
 Nerve cell (neuron) The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord. The basic unit of communication in the nervous system is the nerve cell (neuron). Each nerve cell consists of the cell body, which includes the nucleus, a major branching fiber (axon) and numerous smaller branching fibers (dendrites). The myelin sheath is fatty material that covers, insulates and protects nerves of the brain and spinal cord. Most people infected with the virus that causes polio, called poliovirus, don't get symptoms. Abortive polio About 5% of people with the poliovirus get a mild version of the disease called abortive poliomyelitis. This leads to flu-like symptoms that last 2 to 3 days. These include: 
Fever
Headache
Muscle aches
Sore throat
Stomachache
Loss of appetite
Nausea
Vomiting
 Nonparalytic polio A more severe form of the disease, called nonparalytic polio, affects about 1% of those infected. While the illness lasts longer than a few days, it doesn't cause paralysis. Besides having more-severe flu-like symptoms, nonparalytic polio symptoms may include: 
Neck pain or stiffness
Aches or stiffness in the arms or legs
Severe headache
 A second phase of symptoms may follow, or a person may seem to be getting better for a few days before a second phase starts. These symptoms include: 
Stiffness of the spine and neck
Decreased reflexes
Muscle weakness
 Paralytic polio This most serious form of the disease is rare. The disease begins much like nonparalytic polio. But it progresses to more-severe signs and symptoms, including: 
Intense pain
Extreme sensitivity to touch
Tingling or pricking sensations
Muscles spasms or twitching
Muscles weakness progressing to a limp paralysis
 Any combination of limbs may experience paralysis. But paralysis of one leg is most common, followed by paralysis of one arm. Depending on the severity of disease, other signs or symptoms may include: 
Paralysis of muscles involved in breathing
Difficulty swallowing
 Post-polio syndrome Post-polio syndrome is the appearance of new signs or symptoms or the progression of problems. This usually happens decades after having polio. Common signs and symptoms include: 
Progressive muscle or joint weakness and pain
Fatigue
Muscle wasting
Breathing or swallowing problems
Sleep-related breathing disorders, such as sleep apnea
Lowered tolerance of cold temperatures
