organ

(or’gan) [L. or’ganum; Gr. dpyavoy]. Any part of the body having a special function. acoustic o. Same as o. of Corti. cell-o., a structural part of a cell having some definite function in its life or reproduction, as a nucleus or a centrosome. cement o., the embryonic ti ue which develops into the cement layer of the tooth. ο. of Corti, the terminal acoustic apparatus within the scala media, including the rods of Corti and the auditory cells, with their supporting elements. See ear. enamel-o., a proce of epithelium forming a cap over a dental papilla: from it the enamel is developed. end-o., any distal nerve structure; an end-bulb, -brush, -bud, -plate, -corpuscle, or other terminus of a nerve-branch. 0. of Giraldés, the paradidymus. Golgi’s 0’s, neuromuscular spindles. Sce under spindle. Jacob son’s Ο., a short rudimentary canal extending along the septum of Stensen’s duct. Meyer’s 0., an area of circumvallate papille on either side of the posterior part of the tongue. o. of Rosenmiiller, the parovarium, or epoophoron. Ο. of Ε, an end-organ peculiar to the finger-tips. segmental o., the pronephros, mesonephros, and metaneph- Tos together. sense-0., an organ consisting of a nerve and its termination, by which a stimulus is converted into a sensation. vomeronasal o. Same as Jacob son’s o. Weber’s Ο., the sinus pocularis. Ο᾽Β of Zuckerkandl, ganglia found in late fetal life and a short time after birth at the origin of the inferior mesenteric artery.