- Short and informal reference to the spinal cord, the major column of nerve tissue that is connected to the brain, lies within the vertebral canal, and from which the spinal nerves emerge. The spinal cord and the brain constitute the central nervous system (CNS). The spinal cord consists of nerve fibers that transmit impulses to and from the brain. Like the brain, the spinal cord is covered by three connective-tissue envelopes called the meninges. The space between the outer and middle envelopes is filled with cerebrospinal fluid (CSF), a clear colorless fluid that cushions the spinal cord against jarring shock. Thirty-one pairs of spinal nerves originate in the spinal cord: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, and 1 coccygeal. In the spinal cord, information about internal and external conditions travels up the ascending tracts to the brain. This information is processed by the brain and corresponding responses are induced by nerve impulses traveling down the descending tracts of the spinal cord to stimulate motor neurons or to initiate secretions by glands.
* * *1. In anatomy, any long ropelike structure. A small, cordlike structure composed of several to many longitudinally oriented fibers, vessels, ducts, or combinations thereof. SEE ALSO: chorda. 2. In histopathology, a line of tumor cells only one cell in width. SYN: fasciculus (2) [TA], funiculus [TA], funicle. [L. chorda, a string]- false tendinous cords false chordae tendineae, under chorda.- gangliated c. SYN: sympathetic trunk.- genital c. one of a pair of mesenchymal ridges bulging into the caudal part of the celom of a young embryo and containing the mesonephric and paramesonephric duct.- gonadal cords columns of germinal and follicle cells penetrating centripetally into the embryonic ovarian or testicular cortex.- gubernacular c. the content of the gubernacular canal, usually composed of remnants of dental lamina and connective tissue.- lateral c. of brachial plexus [TA] in the brachial plexus, the bundle of nerve fibers formed by the anterior divisions of the superior and middle trunks which is located lateral to the axillary artery. This c. gives off the lateral pectoral nerve and terminates by dividing into the musculocutaneous nerve and the lateral root of the median nerve. SYN: fasciculus lateralis plexus brachialis [TA].- medial c. of brachial plexus [TA] in the brachial plexus, the bundle of nerve fibers formed by the anterior division of the inferior trunk which lies medial to the axillary artery; it gives off the medial pectoral nerve, the medial brachial cutaneous, and medial antebrachial cutaneous nerves and end by dividing into the medial root of the median nerves and the ulnar nerve. SYN: fasciculus medialis plexus brachialis [TA].- medullary cords 1. cords of dense lymphoid tissue between the sinuses in the medulla of a lymph node; SYN: lymph cords. 2. SYN: rete cords.- nephrogenic c. a longitudinal dorsolateral tract of intermediate mesoderm; the primordium for both mesonephric and metanephric tubules.- nuchal c. loop(s) of umbilical c. around the fetal neck, posing risk of intrauterine hypoxia, fetal distress, or death.- oblique c. of interosseous membrane of forearm [TA] a slender band extending from the lateral part of the coronoid process of the ulna distad and laterad to the radius immediately distal to the bicipital tuberosity. SYN: chorda obliqua membranae interosseae antebrachii [TA], oblique ligament of elbow joint, round ligament of elbow joint, Weitbrecht c., Weitbrecht ligament.- posterior c. of brachial plexus [TA] in the brachial plexus, the bundle of nerve fibers formed by the posterior divisions of the upper, middle and lower trunks which lies posterior to the axillary artery; it gives rise to the upper and lower subscapular and thoracodorsal nerves, terminates by dividing into the axillary, and radial nerves. SYN: fasciculus posterior plexus brachialis [TA].- rete cords primordial cell cords (medullary cords and sex cords) in the embryonic gonads that connect with some of the mesonephric tubules and from which the rete testis of the male and the rete ovarii of the female develop. SYN: medullary cords (2).- sex cords SYN: germinal cords.- spermatic c. [TA] the c. formed by the ductus deferens and its associated structures extending from the deep inguinal ring through the inguinal canal into the scrotum. SEE ALSO: coverings of spermatic c., under covering. SYN: funiculus spermaticus [TA], chorda spermatica, testicular c..- spinal c. [TA] the elongated cylindrical portion of the cerebrospinal axis, or central nervous system, which is contained in the spinal or vertebral canal. SYN: medulla spinalis [TA], chorda spinalis, spinal marrow.- splenic cords the tissue occurring between the venous sinuses in the red pulp of the spleen. SYN: Billroth cords, red pulp cords.- umbilical c. the definitive connecting stalk between the embryo or fetus and the placenta; at birth it is primarily composed of Wharton jelly in which the umbilical vessels are embedded. SYN: chorda umbilicalis, funiculus umbilicalis, funis (1).- c. of umbilical artery [TA] the obliterated umbilical artery that persists as a fibrous c. passing upward alongside the bladder to the umbilicus. SYN: chorda arteriae umbilicalis [TA], ligamentum umbilicale mediale, medial umbilical ligament.- vitelline c. a persistent yolk stalk in the form of a solid c. of tissue connecting ileum to umbilicus. SYN: omphalomesenteric c..* * *Commissioned Officer Residency Deferment; Council of [Emergency Medicine] Residency Directors
* * *cord 'kȯ(ə)rd n1) a long slender flexible material usu. consisting of several strands (as of thread or yarn) woven or twisted together2) a slender flexible anatomical structure (as a nerve) see SPERMATIC CORD, SPINAL CORD, UMBILICAL CORD, VOCAL CORD (1)
* * *n.any long flexible structure, which may be solid or tubular. Examples include the spermatic cord, spinal cord, umbilical cord, and vocal cord.
* * *(kord) [L. chorda; Gr. chordē string] any long, rounded, flexible structure; see also chorda and funiculus.
Medical dictionary. 2011.