The Central Nervous System Cns

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Impulses are transmitted from one neuron to the next through chemical and electrical conduction. Presynaptic neurons conduct impulses toward the synapse while postsynaptic neurons conduct away from the synapse. The electric impulse move from the first neuron, along the axon, to the synapse at the synaptic knobs. Secretion of chemical transmitter into the synaptic nerve depolarizes the membrane of the subsequent neuron. In its unexcited state, a neuron retains a resting membrane potential. When the membrane potential is excited, the arrival of an action potential at the synaptic knob allows the neurotransmitters released into synaptic cleft to trigger an action potential in the postsynaptic neuron (McCance & Huether, 2014).
The central nervous system CNS is the main control center of the body that receives sensory input, organizes and synthesizes it then provides instructions for motor output to the rest of the body. It constitute of the brain and spinal cord. The brain consist of the cerebrum which regulates high level functioning such as thinking, and the cerebellum which maintains coordination. The midbrain, pons and medulla are part of the brain stem and they control lower level functioning such as respiration. The spinal cord joins the body’s main receptors, and functions as a channel for sensory input and motor output.
The peripheral nervous system (PNS) constitute of the cranial and spinal nerves. The PNS provides the connection between internal or external stimuli
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