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Related to costal arch: Left Costal Margin
that portion of the inferior aperture of the thorax formed by the articulated cartilages of the seventh to tenth (that is, false) ribs.
Etymology: L, costa + arcus, bow
an arch formed by the shafts of the ribs.
cos·tal arch(kos'tăl ahrch)
That portion of the inferior aperture of the thorax formed by the articulated cartilages of the seventh to tenth (false) ribs.
a structure of bowlike or curved outline.
arch of aorta
the curving portion between the ascending and descending aorta, giving rise to the brachiocephalic trunk and, in some species, the left common carotid and the left subclavian artery.
paired vessels that run from the ventral to the dorsal aortae through the branchial arches of fishes and amniote embryos. In mammalian development, arches 1 and 2 disappear; 3 joins the common to become the internal carotid artery; 4 becomes the arch of the aorta and joins the aorta and subclavian artery; 5 disappears; 6 forms the pulmonary arteries and, until birth, the ductus arteriosus.
one or more arteries that form an anastomotic connection between two more or less parallel tributaries; found commonly around joints and other moveable parts.
arch arteriosus, arcus arteriosus
a large communicating branch between two arteries.
four pairs of mesenchymal and later cartilaginous columns in the pharyngeal wall which in fish develop into gills and in mammals become modified into structures of the ear and neck.
branchial arch derivatives
derivatives of the arches are first arch (mandible, ossicles), second arch (hyoid apparatus, ear ossicles), third arch (hyoid apparatus), fourth arch (laryngeal cartilages).
the rim to the bony thorax formed by the conjoined asternal ribs and their connecting elastic tissue.
the slender ventral half of the cricoid cartilage of the larynx. The most caudal of the palpable landmarks of the larynx.
the curving structure formed by the crowns of the teeth in their normal position, or by the residual ridge after loss of the teeth.
the v- or y-shaped bone borne on the ventral surface of the tail vertebrae of some animals and which protects blood vessels. Called also chevron bone.
the second branchial arch.
ischial arch, ischiatic arch
the caudal rim of the pelvis formed by the conjunction of the two ischiae. Called also sciatic arch.
lumbocostal arch of the diaphragm
the dorsal part of the diaphragm where it crosses the ventral surface of the psoas muscles. Here it is without any attachment and only serous membranes separate the thoracic and peritoneal cavities.
the first branchial arch, being the rudiment of the maxillary and mandibular regions.
the dorsal vertebral arch.
the arch formed by the roof of the mouth from the teeth on one side to those on the other.
the thick fold of tissue passing from the soft palate to the lateral border of the tongue.
a horizontal fold of pharyngeal mucosa that passes from the soft palate and joins with its opposite fold over the entrance to the esophagus.
a superficial and a deep vascular arch behind the carpus formed by the conjunction of several arteries of the forearm.
the most caudal of the embryonic aortic arches, which become the pulmonary arteries.
the deep palmar arch, especially of horses.
superficial dorsal arch
one of the arterial arches in the foot of carnivores.
the superficial palmar arch, especially of horses.
a linear arched thickening of fascia that provides attachment for some muscles.
the union between the medial and lateral palmar digital arteries, which in horses runs through the solar canal within the distal phalanx.
the dorsal bony arch of a vertebra, composed of paired laminae and pedicles.
the arch formed by the processes of the zygomatic and temporal bones that is the principal origin of the masseter muscle and is particularly broad and prominent in carnivores.