"may be seen where the artery left the optic disc, and is known as Bergmeister's papilla. Hyaloid artery The hyaloid artery is a branch of the ophthalmic artery, which is itself a branch of the internal carotid artery. It is contained within the optic stalk of the eye and extends from the optic disc through the vitreous humor to the lens. Usually fully regressed before birth, its purpose is to supply nutrients to the developing lens in the growing fetus. During the tenth week of development in humans (time varies depending on species), the lens grows independent of a blood"
"Hyaloid canal Hyaloid canal (Cloquet's canal and Stilling's canal) is a small transparent canal running through the vitreous body from the optic nerve disc to the lens. It is formed by an invagination of the hyaloid, a membrane which encloses the vitreous body. In the fetus, the hyaloid canal contains a prolongation of the central artery of the retina, the hyaloid artery, which supplies blood to the developing lens. After birth, the hyaloid canal contains lymph and its purpose is to facilitate changes in the volume of the lens. As the lens expands in positive accommodation, its volume increases. This"
"the retina. Regression of the hyaloid artery leaves a clear central zone through the vitreous humor, called the hyaloid canal or Cloquet's canal. Cloquet's canal is named after the French physician Jules Germain Cloquet (1790–1883) who first described it. Occasionally the artery may not fully regress, resulting in the condition ""persistent hyaloid artery"". More commonly, small remnants of the artery may remain. Free remnants can sometimes be seen as ""floaters"". An anterior remnant of the hyaloid artery can be seen in some people as Mittendorf's dot, a small pinpoint-like scar on the posterior surface of the lens. A posterior remnant"
"Hypoglossal canal The hypoglossal canal is a foramen in the occipital bone of the skull. It is hidden medially and superiorly to each occipital condyle. The hypoglossal nerve traverses the canal. It transmits the hypoglossal nerve from its point of entry near the medulla oblongata to its exit from the base of the skull near the jugular foramen. It lies in the epiphyseal junction between the basiocciput and the jugular process of the occipital bone. The hypoglossal canal has recently been used to try to determine the antiquity of human speech. Researchers have found that hominids who lived as long"
"is known as the carotid sinus or the carotid bulb. The ascending portion of the cervical segment occurs distal to the bulb, when the vessel walls are again parallel. The internal carotid runs vertically upward in the carotid sheath and enters the skull through the carotid canal. During this part of its course, it lies in front of the transverse processes of the upper three cervical vertebrae. It is relatively superficial at its start, where it is contained in the carotid triangle of the neck, and lies behind and medial to the external carotid, overlapped by the sternocleidomastoid muscle, and"
"Carpal tunnel In the human body, the carpal tunnel or carpal canal is the passageway on the palmar side of the wrist that connects the forearm to the hand. The tunnel is bounded by the bones of the wrist and flexor retinaculum from connective tissue. Normally several tendons from the flexor group of forearm muscles and the median nerve pass through it. There are described cases of variable median artery occurrence. The canal is narrow, and when any of the nine long flexor tendons passing through it swell or degenerate, the narrowing of the canal may result in the median"
"Artery of the pterygoid canal The artery of the pterygoid canal (Vidian artery) is an artery in the pterygoid canal, in the head. It usually arises from the external carotid artery, but can arise from either the internal or external carotid artery or serve as an anastomosis between the two. The eponym, Vidian artery, is derived from the Italian surgeon and anatomist Vidus Vidius. In this case; the artery passes backward along the pterygoid canal with the corresponding nerve. It is distributed to the upper part of the pharynx and to the auditory tube, sending into the tympanic cavity a"
"only to the body cavity. The body cavity is itself somewhat restricted, being largely replaced by connective tissue, although it is present as narrow canals within the arms and stalk. Crinoids also possess a separate haemal system, consisting of fluid-filled sinuses within the connective tissue. There is a large plexus of sinuses around the oesophagus, with branches extending down to a mass of glandular tissue at the base of the calyx. These various fluid-filled spaces, in addition to transporting nutrients around the body, also function as both a respiratory and an excretory system. Oxygen is absorbed primarily through the tube"
"Foramen lacerum The foramen lacerum () is a triangular hole in the base of skull, located between the sphenoid, the apex of the petrous temporal and the basilar part of the occipital. The foramen lacerum () is a triangular hole in the base of skull located between the sphenoid, apex of petrous temporal and basilar part of occipital. It is the juncture of the petroclival, sphenopetrosal, and pterygosphenoidal sutures. The foramen lacerum is a foramen situated anteromedial to the carotid canal. The foramen lacerum fills with cartilage after birth. The artery of pterygoid canal, the nerve of pterygoid canal and"
"Condylar canal The condylar canal (or condyloid canal) is a canal in the condyloid fossa of the lateral parts of occipital bone behind the occipital condyle. Resection of the rectus capitis posterior major and minor muscles reveals the bony recess leading to the condylar canal, which is situated posterior and lateral to the occipital condyle. It is immediately superior to the extradural vertebral artery, which makes a loop above the posterior C1 ring to enter the foramen magnum. The anteriomedial wall of the condylar canal thickens to join the foramen magnum rim and connect to the occipital condyle. Through the"
"Carotid canal The carotid canal is the passageway in the temporal bone through which the internal carotid artery enters the middle cranial fossa from the neck. The canal starts on the inferior surface of the temporal bone at the external opening of the carotid canal (also referred to as the carotid foramen). The canal ascends at first superiorly, and then, making a bend, runs anteromedially. The canal's internal opening is near the foramen lacerum, above which the internal carotid artery passes on its way anteriorly to the cavernous sinus. The carotid canal allows the internal carotid artery to pass into"
"against a bicycle handlebar. Ulnar canal The ulnar canal or ulnar tunnel (also known as Guyon's canal or tunnel) is a semi-rigid longitudinal canal in the wrist that allows passage of the ulnar artery and ulnar nerve into the hand. The roof of the canal is made up of the superficial palmar carpal ligament, while the deeper flexor retinaculum and hypothenar muscles comprise the floor. The space is medially bounded by the pisiform and pisohamate ligament more proximally, and laterally bounded by the hook of the hamate more distally. It is approximately 4 cm long, beginning proximally at the transverse"
"Hyalocyte Hyalocytes, also known as vitreous cells, are cells of the vitreous body, which is the clear gel that fills the space between the lens and the retina of the eye. Hyalocytes occur in the peripheral part of the vitreous body, and may produce hyaluronic acid, collagen, fibrils, and hyaluronan. Hyalocytes are star-shaped (stellate) cells with oval nuclei. The development of the vitreous is organized into three stages: primary, secondary, and tertiary. During the primary stage, which occurs from 3–6 weeks, the basic components of the vitreous begin to form from the mesenchyme embryonic cell layer. Hyalocytes likely develop from"
"condylar canal, the occipital emissary vein connects to the venous system including the suboccipital venous plexus, occipital sinus and sigmoid sinus. It is not always present, and can have variations of being a single canal or multiple smaller canals in cluster. Condylar canal The condylar canal (or condyloid canal) is a canal in the condyloid fossa of the lateral parts of occipital bone behind the occipital condyle. Resection of the rectus capitis posterior major and minor muscles reveals the bony recess leading to the condylar canal, which is situated posterior and lateral to the occipital condyle. It is immediately superior"
"Anal canal is divided into three parts. The zona columnaris is the upper half of the canal and is lined by simple columnar epithelium. The lower half of the anal canal, below the pectinate line, is divided into two zones separated by Hilton's white line. The two parts are the zona hemorrhagica and zona cutanea, lined by stratified squamous non-keratinized and stratified squamous keratinized epithelium, respectively. In humans it is approximately 2.5 to 4 cm long, extending from the anorectal junction to the anus. It is directed downwards and backwards. It is surrounded by inner involuntary and outer voluntary sphincters"
"Ulnar canal The ulnar canal or ulnar tunnel (also known as Guyon's canal or tunnel) is a semi-rigid longitudinal canal in the wrist that allows passage of the ulnar artery and ulnar nerve into the hand. The roof of the canal is made up of the superficial palmar carpal ligament, while the deeper flexor retinaculum and hypothenar muscles comprise the floor. The space is medially bounded by the pisiform and pisohamate ligament more proximally, and laterally bounded by the hook of the hamate more distally. It is approximately 4 cm long, beginning proximally at the transverse carpal ligament and ending"
"Choroid The choroid, also known as the choroidea or choroid coat, is the vascular layer of the eye, containing connective tissues, and lying between the retina and the sclera. The human choroid is thickest at the far extreme rear of the eye (at 0.2 mm), while in the outlying areas it narrows to 0.1 mm. The choroid provides oxygen and nourishment to the outer layers of the retina. Along with the ciliary body and iris, the choroid forms the uveal tract. The structure of the choroid is generally divided into four layers (classified in order of furthest away from the"
"the vascular primary vitreous. Hyalocyte Hyalocytes, also known as vitreous cells, are cells of the vitreous body, which is the clear gel that fills the space between the lens and the retina of the eye. Hyalocytes occur in the peripheral part of the vitreous body, and may produce hyaluronic acid, collagen, fibrils, and hyaluronan. Hyalocytes are star-shaped (stellate) cells with oval nuclei. The development of the vitreous is organized into three stages: primary, secondary, and tertiary. During the primary stage, which occurs from 3–6 weeks, the basic components of the vitreous begin to form from the mesenchyme embryonic cell layer."
"the cranium, as well as the carotid plexus of nerves traveling on the artery. Sympathetics to the head from the superior cervical ganglion also pass through the carotid canal. They have several motor functions: raise the eyelid (superior tarsal muscle), dilate pupil, innervate sweat glands of face and scalp and constricts blood vessels in the head. Carotid canal The carotid canal is the passageway in the temporal bone through which the internal carotid artery enters the middle cranial fossa from the neck. The canal starts on the inferior surface of the temporal bone at the external opening of the carotid"
"Greater palatine canal The greater palatine canal (or pterygopalatine canal) is a passage in the skull that transmits the descending palatine artery, vein, and greater and lesser palatine nerves between the pterygopalatine fossa and the oral cavity. The greater palatine canal starts on the inferior aspect of the pterygopalatine fossa. It goes through the maxilla and palatine bones to reach the palate, ending at the greater palatine foramen. From this canal, accessory canals branch off; these are known as the lesser palatine canals. The canal is formed by a vertical groove on the posterior part of the maxillary surface of"
"in the gland is the facial artery and its glandular branches. Beneath the gland, on the surface of the Mylohyoideus, are the submental artery and the mylohyoid artery and nerve. The posterior part of this triangle contains the external carotid artery, ascending deeply in the substance of the parotid gland This vessel lies here in front of, and superficial to, the external carotid, being crossed by the facial nerve, and gives off in its course the posterior auricular, superficial temporal, and internal maxillary branches: more deeply are the internal carotid, the internal jugular vein, and the vagus nerve, separated from"
"Palatovaginal canal The palatovaginal canal (also pharyngeal canal) is a canal between the sphenoid bone and the palatine bone that connects the nasopharynx with the pterygopalatine fossa. An inconstant vomerovaginal canal may lie between the ala of the vomer and the vaginal process of the sphenoid bone, medial to the palatovaginal canal, and lead into the anterior end of the palatovaginal canal. It transmits the pharyngeal branch of the third part of the maxillary artery. The palatovaginal canal contains the pharyngeal nerve from the pterygopalatine ganglion and the pharyngeal branch of the maxillary artery. The pharyngeal nerve conveys sensory information"
"Femoral canal In human anatomy of the leg, the femoral sheath has three compartments. The lateral compartment contains the femoral artery, the intermediate compartment contains the femoral vein, and the medial and smallest compartment is called the femoral canal. The femoral canal contains efferent lymphatic vessels and a lymph node embedded in a small amount of areolar tissue. It is conical in shape and is about 2 cm long. The femoral canal is bordered: It contains the lymph node of Cloquet. It should not be confused with the nearby adductor canal. The entrance to the femoral canal is the femoral"
"Hyoid bone The hyoid bone (lingual bone or tongue-bone) () is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies at the level of the base of the mandible in the front and the third cervical vertebra (C3) behind. Unlike other bones, the hyoid is only distantly articulated to other bones by muscles or ligaments. The hyoid is anchored by muscles from the anterior, posterior and inferior directions, and aids in tongue movement and swallowing. The hyoid bone provides attachment to the muscles of the floor of"
"Optic canal The ""optic foramen"" is the opening to the optic canal. The canal is located in the sphenoid bone; it is bounded medially by the body of the sphenoid and laterally by the lesser wing of the sphenoid. The superior surface of the sphenoid bone is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the chiasmatic groove (optic groove), above and behind which lies the optic chiasma; the groove ends on either side in the optic foramen, which transmits the optic nerve and ophthalmic artery (with accompanying sympathetic nerve fibres) into the"
"Adductor canal The adductor canal (subsartorial or Hunter’s canal) is an aponeurotic tunnel in the middle third of the thigh, extending from the apex of the femoral triangle to the opening in the adductor magnus, the adductor hiatus. It is an intermuscular cleft situated on the medial aspect of the middle third of the thigh on anterior compartment of thigh, and has the following boundaries: It is covered in by a strong aponeurosis which extends from the vastus medialis, across the femoral vessels to the adductor longus and magnus. The canal contains the superficial femoral artery, femoral vein, and branches"
"that produce eggs or sperm, and photocytes that produce bioluminescence. The side furthest from the organ is covered with ciliated cells that circulate water through the canals, punctuated by ciliary rosettes, pores that are surrounded by double whorls of cilia and connect to the mesoglea. When prey is swallowed, it is liquefied in the pharynx by enzymes and by muscular contractions of the pharynx. The resulting slurry is wafted through the canal system by the beating of the cilia, and digested by the nutritive cells. The ciliary rosettes in the canals may help to transport nutrients to muscles in the"
"Krav Maga. Carotid sinus In human anatomy, the carotid sinus is a dilated area at the base of the internal carotid artery just superior to the bifurcation of the internal carotid and external carotid at the level of the superior border of thyroid cartilage. The carotid sinus extends from the bifurcation to the ""true"" internal carotid artery. The carotid sinus is sensitive to pressure changes in the arterial blood at this level. It is the major baroreception site in humans and most mammals. The carotid sinus is the reflex area of the carotid artery, consisting of various nerve receptors for"
"canal. These are located classically at left lateral, right anterior, and right posterior positions. They are composed of neither arteries nor veins, but blood vessels called sinusoids, connective tissue, and smooth muscle. Sinusoids do not have muscle tissue in their walls, as veins do. This set of blood vessels is known as the hemorrhoidal plexus. Hemorrhoid cushions are important for continence. They contribute to 15–20% of anal closure pressure at rest and protect the internal and external anal sphincter muscles during the passage of stool. When a person bears down, the intra-abdominal pressure grows, and hemorrhoid cushions increase in size,"
"Anal canal The anal canal is the terminal part of the large intestine. It is situated between the rectum and anus, below the level of the pelvic diaphragm. In humans it is approximately 2.5 to 4 cm (0.98-1.58 in) long. It lies in the anal triangle of perineum in between the right and left ischioanal fossa. The anal canal is the short terminal portion of the rectum through which wastes from the large intestine are excreted from the body. The ring at the terminal portion of the anal canal is called the anus. The anal canal is between 2.5 cm"
"tail, and fins of tadpoles. Iodine, via iodolipids, has favored the evolution of terrestrial animal species and has likely played a crucial role in the evolution of the human brain. Thyroid The thyroid gland, or simply the thyroid, is an endocrine gland in the neck, consisting of two lobes connected by an . It is found at the front of the neck, below the Adam's apple. The thyroid gland secretes thyroid hormones, which primarily influence the metabolic rate and protein synthesis. The hormones also have many other effects including those on development. The thyroid hormones triiodothyronine (T) and thyroxine (T)"
"the fluids. At the base of each canal, the bony region of the canal is enlarged which opens into the utricle and has a dilated sac at one end called the osseous ampullae. Within the ampulla is a mound of hair cells and supporting cells called crista ampullaris. These hair cells have many cytoplasmic projections on the apical surface called stereocilia which are embedded in a gelatinous structure called the cupula. As the head rotates the duct moves but the endolymph lags behind owing to inertia. This deflects the cupula and bends the stereocilia within. The bending of these stereocilia"
"Inguinal canal The inguinal canals are the two passages in the anterior abdominal wall which in males convey the spermatic cords and in females the round ligament of uterus. The inguinal canals are larger and more prominent in males. There is one inguinal canal on each side of the midline. The inguinal canals are situated just above the medial half of the inguinal ligament. In both sexes the canals transmit the ilioinguinal nerves. The canals are approximately 3.75 to 4 cm long. , angled anteroinferiorly and medially. A first-order approximation is to visualize each canal as a cylinder. To help"