motor nerve


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Related to motor nerve: somatic motor neuron

nerve

 [nerv]
a macroscopic cordlike structure of the body, comprising a collection of nerve fibers that convey impulses between a part of the central nervous system and some other body region. See Appendix 2-6 and see color plates.

Depending on their function, nerves are known as sensory, motor, or mixed. Sensory nerves, sometimes called afferent nerves, carry information from the outside world, such as sensations of heat, cold, and pain, to the brain and spinal cord. Motor nerves, or efferent nerves, transmit impulses from the brain and spinal cord to the muscles. Mixed nerves are composed of both motor and sensory fibers, and transmit messages in both directions at once.

Together, the nerves make up the peripheral nervous system, as distinguished from the central nervous system (brain and spinal cord). There are 12 pairs of cranial nerves, which carry messages to and from the brain. Spinal nerves arise from the spinal cord and pass out between the vertebrae; there are 31 pairs, 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. The various nerve fibers and cells that make up the autonomic nervous system innervate the glands, heart, blood vessels, and involuntary muscles of the internal organs.
Details of structure of components of nerve tissue.
accelerator n's the cardiac sympathetic nerves, which, when stimulated, accelerate the action of the heart.
acoustic nerve vestibulocochlear nerve; see anatomic Table of Nerves in the Appendices.
afferent nerve any nerve that transmits impulses from the periphery toward the central nervous system, such as a sensory nerve. See also neuron.
articular nerve any mixed peripheral nerve that supplies a joint and its associated structures.
auditory nerve vestibulocochlear nerve; see anatomic Table of Nerves in the Appendices.
autonomic nerve any nerve of the autonomic nervous system; called also visceral nerve.
cranial n's see cranial nerves.
cutaneous nerve any mixed peripheral nerve that supplies a region of the skin. See anatomic Table of Nerves in the Appendices.
depressor nerve
1. a nerve that lessens the activity of an organ.
2. an afferent nerve whose stimulation causes a fall in blood pressure.
efferent nerve any nerve that carries impulses from the central nervous system toward the periphery, such as a motor nerve. See also neuron.
excitor nerve one that transmits impulses resulting in an increase in functional activity.
excitoreflex nerve a visceral nerve that produces reflex action.
fusimotor n's those that innervate the intrafusal fibers of the muscle spindle.
gangliated nerve any nerve of the sympathetic nervous system.
inhibitory nerve one that transmits impulses resulting in a decrease in functional activity.
medullated nerve myelinated nerve.
mixed nerve (nerve of mixed fibers) a nerve composed of both sensory (afferent) and motor (efferent) fibers.
motor nerve a peripheral efferent nerve that stimulates muscle contraction.
myelinated nerve one whose axons are encased in a myelin sheath; called also medullated nerve.
peripheral nerve any nerve outside the central nervous system.
pilomotor n's those that supply the arrector muscles of hair.
pressor nerve an afferent nerve whose irritation stimulates a vasomotor center and increases intravascular tension.
sciatic nerve see sciatic nerve.
secretory nerve an efferent nerve whose stimulation increases vascular activity.
sensory nerve a peripheral nerve that conducts impulses from a sense organ to the spinal cord or brain. See also neuron.
somatic n's the sensory and motor nerves supplying skeletal muscle and somatic tissues.
spinal n's the 31 pairs of nerves arising from the spinal cord and passing out through the vertebrae; there are eight cervical, twelve thoracic, five lumbar, five sacral, and one coccygeal. , and see anatomic Table of Nerves in the Appendices.
Spinal nerves emerging from the spinal cord through the intervertebral foramina with muscles or muscle movements listed for specific levels. From McQuillan et al., 2002.
splanchnic n's those of the blood vessels and viscera, especially the visceral branches of the thoracic, abdominal (lumbar), and pelvic parts of the sympathetic trunks. See Appendix 3-5.
sudomotor n's those that innervate the sweat glands.
sympathetic n's
2. any nerve of the sympathetic nervous system.
trophic nerve one concerned with regulation of nutrition.
unmyelinated nerve one whose axons are not encased in a myelin sheath.
vasoconstrictor nerve one whose stimulation causes contraction of blood vessels.
vasodilator nerve one whose stimulation causes dilation of blood vessels.
vasomotor nerve one concerned in controlling the caliber of vessels, whether as a vasoconstrictor or vasodilator.
vasosensory nerve any nerve supplying sensory fibers to the vessels.
visceral nerve autonomic nerve.

mo·tor nerve

[TA]
a nerve composed mostly or entirely of efferent (motor) nerve fibers conveying impulses that excites muscular contraction; motor nerves in the autonomic nervous system also elicit secretions from glandular epithelia.
Synonym(s): nervus motorius [TA]

motor nerve

an efferent nerve that conveys impulses to motor endplates or another terminal and is mainly responsible for stimulating muscles and glands.

mo·tor nerve

(mō'tŏr nĕrv) [TA]
An efferent nerve conveying an impulse that excites muscular contraction; motor nerves in the autonomic nervous system also elicit secretions from glandular epithelia.

Motor nerve

Motor or efferent nerve cells carry impulses from the brain to muscle or organ tissue.

motor nerve

general term for any nerve consisting of efferent nerve fibres en route to effectors (muscles, glands).

mo·tor nerve

(mō'tŏr nĕrv) [TA]
Nerve composed mostly or entirely of efferent (motor) nerve fibers conveying impulses that excite muscular contraction; those in autonomic nervous system also elicit secretions from glandular epithelia.
References in periodicals archive ?
Effects of age on temperature-related variation in motor nerve conduction velocity in healthy chickens.
Further, skeletal muscle cramps at any site may arise from the intramuscular portion of the motor nerve terminal itself[10] or from the peripheral portion of the nerve.
al, Processed Nerve Allografts for Peripheral Nerve Reconstruction: A Multicenter Study of Utilization and Outcomes in Sensory, Mixed, and Motor Nerve Reconstructions.
By touching skin on the head of the tadpole and applying cellular neurophysiology and anatomy techniques, the scientists identified nerve cells that detect the touch on the skin, two types of brain nerve cells which pass on the signal, and the motor nerve cells that control the swimming muscles.
The measurements of median nerve sensory distal latency, sensory amplitude, velocity of sensory nerve conduction, motor distal latency, motor amplitude, and velocity of motor nerve conduction were done using standard techniques.
Motor nerve conduction velocities in the left median, left ulnar, and bilateral tibial and peroneal nerves were normal, as were terminal motor latencies.
Motor nerve function had only partially recovered 12 months after the accident, at which time sensory nerve function was still severely impaired, particularly in the hand.
Localization of adductor and abductor motor nerve fibers to the larynx.
Each lower motor nerve has a cell body in the spinal cord that sends its own "wire" or axon out of the spinal cord.
These renegade charged molecules eventually cause motor nerve cells - and the muscles they control -- to die, says James O.
AxoGen announced today the presentation of data from a clinical registry study entitled, Analysis of Quantitative Endpoints from a Multicenter Retrospective Registry Study on the Use of Acellular Nerve Grafts for Sensory, Mixed and Motor Nerve Reconstructions.
MOTOR Motor means movement so a motor nerve runs from the spinal cord to a muscle or a muscle group.