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plexus

 
Dictionary: plex·us   (plĕk'səs) pronunciation
n., pl., plexus, or -us·es.
  1. A structure in the form of a network, especially of nerves, blood vessels, or lymphatics: the cardiac plexus; the pelvic plexus.
  2. A combination of interlaced parts; a network.

[New Latin, from Latin, braid, from past participle of plectere, to plait.]


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Dental Dictionary: plexus
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(plek′sus)
n

A network or tangle, especially of nerves, lymphatics, or veins.

A network of blood vessels or nerve fibres. There are five major nerve plexuses; the brachial, cervical, coccygeal, lumbar, and sacral plexuses. Some of their fibres carry sensory messages to the central nervous system (CNS), and others carry motor impulses away from the CNS to the effector organs, such as muscles.

Pl. plexus, plexuses [L.] a network or tangle, chiefly of veins or nerves.

  • brachial p. — see brachial plexus.
  • cardiac p. — the plexus around the base of the heart, chiefly in the epicardium, formed by cardiac branches from the vagus nerves and the sympathetic trunks and ganglia, and made up of sympathetic, parasympathetic and visceral afferent fibers that innervate the heart.
  • carotid p's — nerve plexuses surrounding the common, external and internal carotid arteries.
  • celiac p. — a plexus of autonomic fibers and sympathetic nerve ganglia which surround the origin of the celiac artery, and supply the abdominal viscera.
  • celiacomesenteric p. — a plexus of autonomic nerve fibers and sympathetic ganglia around the origin of the celiac and cranial mesenteric arteries; called also solar plexus.
  • cervical p. — a network of nerve fibers formed by the first four cervical nerves and supplying the structures in the region of the neck.
  • choroid p. — infoldings of blood vessels of the pia mater covered by a thin coat of ependymal cells that form tufted projections into the third, fourth, and lateral ventricles of the brain; they secrete the cerebrospinal fluid.
  • coccygeal p. — a nerve plexus formed by the ventral branches of the coccygeal and last sacral nerves.
  • coronary p. — a venous plexus within the coronet of the hoof.
  • cutaneous p's — superficial, middle and deep, inter-communicating plexuses of blood vessels are identified as supplying blood to haired skin.
  • cystic p. — a nerve plexus near the gallbladder.
  • dental p. — either of two plexuses (inferior and superior) of nerve fibers, one from the inferior alveolar nerve, situated around the roots of the lower teeth, and the other from the superior alveolar nerve, situated around the roots of the upper teeth.
  • gonadal p. — the collection of parasympathetic and sympathetic nerves to the gonads.
  • hoof p. — plexus of veins draining the hoof region in the horse.
  • lumbar p. — see lumbar plexus.
  • lumbosacral p. — see lumbosacral plexus.
  • mesenteric p. — parasympathetic and sympathetic nerve supply to the abdominal organs.
  • myenteric p. — see auerbach plexus.
  • nerve p. — a plexus composed of intermingled nerve fibers.
  • pampiniform p. — 1. a plexus of veins from the testis and the epididymis, constituting part of the spermatic cord.
  • — 2. a plexus of ovarian veins in the broad ligament of the uterus.
  • parametrial p. — the venous plexus within the broad ligament providing venous drainage to the uterus and vagina.
  • p. papilloma — see plexus papilloma.
  • pulmonary p. — the array of autonomic nerves which supply the lungs.
  • renal p. — autonomic nerve supply to the kidney.
  • sacral p. — a plexus arising from the ventral branches of the last few lumbar and first few sacral spinal nerves.
  • solar p. — see celiacomesenteric plexus (above).
  • tympanic p. — a network of nerve fibers supplying the mucous lining of the tympanum and auditory tube.
Wikipedia: Plexus
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A plexus is a network. In biology the term plexus has multiple meanings:

Contents

Nervous system

In many animals the processes of neurons join together to form a plexus or nerve net.

In vertebrates

In vertebrates, a plexus is an area where nerves branch and rejoin. The electrical signals do not mix - rather, the fibres travel together with their electrical signals separate. The brachial plexus is an example. It is made up of the spinal nerves which enter the upper limb.

Almost a hundred such plexuses have been described in the human body, but the four primary nerve plexuses are the cervical plexus, brachial plexus, lumbar plexus, and the sacral plexus.

In invertebrates

Plexuses is the characteristic form of nervous system in the coelenterates and persists with modifications in the flatworms. The nerves of the radially symmetric echinoderms also take this form, where a plexus underlies the ectoderm of these animals and deeper in the body other nerve cells form plexuses of limited extent.

Circulatory system

A plexus is also a network of blood vessels. The choroid plexus of the brain is an example.

In a vascular plexus, the contents of the vessels mix. A plexus allows blood to flow via multiple routes. If one branch of the plexus is obstructed, the blood may flow via the open branches.


Translations: Plexus
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Dansk (Danish)
n. - fletværk, net

Nederlands (Dutch)
netwerk van bloedvaten of zenuwen

Français (French)
n. - plexus

Deutsch (German)
n. - Plexus

Ελληνική (Greek)
n. - πλέγμα

Italiano (Italian)
plesso

Português (Portuguese)
n. - plexo (m), teia (f)

Русский (Russian)
сплетение

Español (Spanish)
n. - plexo, entrelazamiento

Svenska (Swedish)
n. - nät, nätverk

中文(简体)(Chinese (Simplified))

中文(繁體)(Chinese (Traditional))
n. - 叢

한국어 (Korean)
n. - (신경, 혈관의) 망, 망상조직

日本語 (Japanese)
n. - 叢, 網状構造, もつれ, 網状組織

العربيه (Arabic)
‏(الاسم) شبكه مواصلات او سكه حديديه وما إلى ذلك, ضفيرة‏

עברית (Hebrew)
n. - ‮מקלעת, רשת עצבים וכלי-דם‬


 
 

 

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Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.  Read more
Dental Dictionary. Mosby's Dental Dictionary. Copyright © 2004 by Elsevier, Inc. All rights reserved.  Read more
Sports Science and Medicine. The Oxford Dictionary of Sports Science & Medicine. Copyright © Michael Kent 1998, 2006, 2007. All rights reserved.  Read more
Veterinary Dictionary. Saunders Comprehensive Veterinary Dictionary 3rd Edition. Copyright © 2007 by D.C. Blood, V.P. Studdert and C.C. Gay, Elsevier. All rights reserved.  Read more
Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Plexus" Read more
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