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Killian's nasal bone gouge: bayonet shaped; removing parts of the nasal septum: Myringotome: used to cut the ear drum: Grommet stapedectomy set: used in surgeries of the ear drum: Tracheostomy tube: used in tracheostomy to bypass the airway above its point of insertion, due to any reason •Fuller's bi-valve type
Pharyngeal teeth are teeth in the pharyngeal arch of the throat of cyprinids, suckers, and a number of other fish species otherwise lacking teeth. [ 1 ] Many popular aquarium fish such as goldfish and loaches have these structures.
The mouths of these fish are most commonly located on the underside of their head (subterminal), with thick, fleshy lips.Most species are less than 60 cm (2.0 ft) in length, but the largest species (Ictiobus and Myxocyprinus) can surpass 100 cm (3.3 ft).
This sinus is a common place for food particles to become trapped; if foreign material becomes lodged in the piriform fossa of an infant, it may be retrieved nonsurgically. If the area is injured (e.g., by a fish bone), it can give the sensation of food stuck in the subject's throat. [2]
Most fish species with pharyngeal teeth do not have extendable pharyngeal jaws. A particularly notable exception is the highly mobile pharyngeal jaw of the moray eels.These are possibly a response to their inability to swallow as other fishes do by creating a negative pressure in the mouth, perhaps induced by their restricted environmental niche (burrows) or in the air in the intertidal zone. [10]
Some fish like carp and zebrafish have pharyngeal teeth only. [30] [31] Sea horses, pipefish, and adult sturgeon have no teeth of any type. In fish, Hox gene expression regulates mechanisms for tooth initiation. [32] [33] While both sharks and bony fish continuously produce new teeth throughout their lives, they do so via different mechanism.
Some fish species have a second set of jaws in their throat, known as pharyngeal jaws, which develop using the same genetic pathways involved in oral jaw formation. [6] During embryonic development, a series of pharyngeal arch pairs form. These project forward from the back of the embryo toward the front of the face and neck.
Fish bone is any bony tissue in a fish, although in common usage the term refers specifically to delicate parts of the non-vertebral skeleton of such as ribs, fin spines and intramuscular bones. Not all fish have fish bones in this sense; for instance, eels and anglerfish do not possess bones other than the cranium and the vertebrae.