BIO SCI E109 Chapter Notes - Chapter 7: Skeletal Muscle, Motor Neuron, Neuropeptide Y
4 Oct 2016
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Neural circuits : the cns contains billions of neurons organized into complicated networks called neural circuits. Divergence: a synaptic arrangement in which the synaptic end bulbs of one presynaptic neuron terminate on several postsynaptic neurons. Example: small groups of neurons in the brain that governs a particular body movement stimulates a larger number of neurons in the spinal cord. Sensory signals are also arranged in diverging circuits, Convergence: a synaptic movement in which the synaptic end bulbs of several presynaptic neurons terminate on one postsynaptic neuron. Example: a single motor neuron that synapses with skeletal muscle fivers at nmj(neuromuscular junctions) receive input from several pathways that originate in different brain fegions. This arrangement sends action potentials back through the circuit again and again, the output signal may last from a few seconds to many hours. Example: breathing, coordinated muscular activities, waking up, and short-term memory.
