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Fig.1 ( below ): A diagram showing some very important nerves and nerve cluster regions of the body. A Highly Simplified Guide to the Nervous System.
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Fig.1 (below): A diagram showing some very important nerves and nerve cluster regions of the body. A Highly Simplified Guide to the Nervous System Fig.2 (above): The brain controls the conscious action of the body through the transduction of electrical & chemical signals through nerves to reach the entirety of the body.
What is a nerve? • The type of nerve cells that carry out the most important function of the nervous system are generally called neurons. • These neurons exist to transmit information andcommands between the brain, spine, and rest of the body.
What is a signal? • Neuronal signal transduction involves the transmission of a chain of alternating electrical currents and special chemicals called a signal. • Signals are responsible for all of our sensory and cognitive functions. • The act of reading this sentence is accomplished by signaling of information from the eyes to the brain, rapid signaling within the brain in order to interpret the sight of the letters, followed by the brain achieving understanding of the meaning.
Electrochemical Signaling (Optional) Fig.4 (left): As signals are transmitted from neuron to neuron down the length of the body, the signal’s physical form alternates between an electrical impulse when traveling the long, main body of the neuron – until it reaches the synapse; or connecting point between neurons. At that point, it is converted into a chemical burst of neurotransmitters which cross the synapse and return to electrical form.
The CNS and PNS (1 of 2) • The nervous system is divided into two primary subsystems… • The Central Nervous System is made up of the brain and spinal chord. This acts as your body’s command & control center. Fig.3 (right): The most critical functions of the brain and body are carried out within specific regions of the CNS.
The CNS and PNS, cont’d (2 of 2) • The Peripheral Nervous System is composed of all the nerve cells throughout the rest of the body. Fig.4 (right): The functions of most organs, movement of the muscles, and functions such as respiration and hormone release are all functions of the PNS.
Fig.7 (below& right): Synapses are located at the tips of both dendrites and axon terminals, along with their payload of neurotransmitters.