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sensory impulseclick to hear

Electrical signal propagated along the nerve fibers (axons) enabling the nerve cells to communicate and to transmit messages within the organism.
sensory impulse motor end plate white matter gray matter muscle fiber sensory neuron sense receptor skin spinal cord synapse motor root motor neuron spinal nerve protoneuron spinal ganglion sensory root

motor end plate click to hear

Contact zone between the axonal end of the motor neuron and the muscle fiber that causes muscle movement.

white matter click to hear

Section of the spinal cord made up of nerve fibers (axons) and surrounding the gray matter.

gray matter click to hear

Central part of the spinal cord primarily made of the cell bodies of neurons.

muscle fiber click to hear

Component tissue of the muscle; it contracts in response to a nerve impulse from the central nervous system.

sensory neuron click to hear

Neuron transmitting information gathered by sensory receptors to the central nervous system.

sense receptor click to hear

Peripheral terminal of the sensory neuron receiving a stimulus (touch, noise or other) and transmitting it to the spinal cord in the form of nerve impulses.

skin click to hear

The body’s outer protective casing whose internal layer (dermis) is rich in veins and nerves.

spinal cord click to hear

Part of the central nervous system located in the spinal column; it receives and transmits nerve information and initiates reflex actions.

synapse click to hear

Contact zone between two neurons through which nerve impulses are transmitted.

motor root click to hear

Bundle of motor nerve fibers (axons) communicating information from the spinal cord to the periphery of the body, especially the muscles.

motor neuron click to hear

Neuron conducting nerve impulses from the central nervous system to the peripheral organs, such as the muscles.

spinal nerve click to hear

Nerve formed by the union of the sensory and motor roots; it communicates nerve messages between the spinal cord and the various parts of the organism.

protoneuron click to hear

First neuron of the sensory tract; it transmits information from a sensory organ to the spinal cord.

spinal ganglion click to hear

Bulge of the posterior sensory root of the spinal nerve; it encloses the cell bodies of the neuron sensors.

sensory root click to hear

Bundle of sensory nerve fibers (axons) communicating information from the periphery of the body to the spinal cord.