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a longitudinal assemblage of tissues or organs, especially a number of anatomic structures arranged in series and serving a common function, such as the gastrointestinal or urinary tract; also used in reference to a bundle (or fasciculus) of nerve fibers having a common origin, function, and termination within the central nervous system.
alimentary tract alimentary canal.
biliary tract the organs, ducts, and other structures that participate in secretion (the liver), storage (the gallbladder), and delivery (hepatic and bile ducts) of bile into the duodenum. See illustration.
corticospinal t's two groups of nerve fibers (the anterior and lateral corticospinal tracts) that originate in the cerebral cortex and run through the spinal cord.
digestive tract alimentary canal.
dorsolateral tract a group of nerve fibers in the lateral funiculus of the spinal cord dorsal to the posterior column.
extrapyramidal tract extrapyramidal system.
gastrointestinal tract the stomach and intestine in continuity; see also digestive system.
iliotibial tract a thickened longitudinal band of fascia lata extending from the tensor muscle downward to the lateral condyle of the tibia.
intestinal tract see intestinal tract.
optic tract the nerve tract proceeding backward from the optic chiasm, around the cerebral peduncle, and dividing into a lateral and medial root, which end in the superior colliculus and lateral geniculate body, respectively.
pyramidal t's collections of motor nerve fibers arising in the brain and passing down through the spinal cord to motor cells in the anterior horns.
respiratory tract respiratory system.
urinary tract the organs and passageways concerned in the production and excretion of urine from the kidneys to the urinary meatus; see also urinary system.
uveal tract the vascular tunic of the eye, comprising the choroid, ciliary body, and iris.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
vascular layer of eyeball[TA]
the vascular, pigmentary, or middle coat of the eye, comprising the choroid, ciliary body, and iris.
Synonym(s): tunica vasculosa bulbi [TA], Haller tunica vasculosa, tunica vasculosa oculi, uvea, uveal tract, vascular tunic of eye
Farlex Partner Medical Dictionary © Farlex 2012
The pigmented membrane that lines the back of the retina of the eye and extends forward to include the iris. The uveal tract is sometimes called the uvea and has three parts: the iris, the choroid, and the ciliary body.
Mentioned in: Uveitis
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.
The vascular tunic of the eye, consisting of the choroid, ciliary body and the iris. The last two structures are usually considered to form the anterior uvea. The uvea contains most of the blood supply (Fig. U2). Syn. uveal tract; vascular tunic of the eye. See uveitis; vortex vein.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann