Each of two openings from the nasal cavity to the throat
Choana
Lateral wall of nasal cavity.
Dissection of the muscles of the palate from behind. (Choanae visible at center top.)
Details
Identifiers
Latin
choana
TA98
A02.1.00.096
TA2
501
FMA
76585
Anatomical terminology
[edit on Wikidata]
The choanae (internal nostrils) of a cat, indicated by the dashed lines and bounded by the vomer (blue gray) and the palatine bone (orange)
The choanae (sg.: choana), posterior nasal apertures or internal nostrils are two openings found at the back of the nasal passage between the nasal cavity and the pharynx, in humans and other mammals (as well as crocodilians and most skinks). They are considered one of the most important synapomorphies of tetrapodomorphs, that allowed the passage from water to land.[1]
In animals with secondary palates, they allow breathing when the mouth is closed.[2] In tetrapods without secondary palates their function relates primarily to olfaction (sense of smell).
The choanae are separated in two by the vomer.
^Clack, Jennifer (2012). Gaining Ground: The Origin and Evolution of Tetrapods. Indiana University Press. p. 74. ISBN 978-0-253-35675-8. Retrieved 5 August 2015.
^Janvier, Philippe (2004) "Wandering nostrils". Nature, 432 (7013): 23–24. doi:10.1038/432023a
The choanae (sg.: choana), posterior nasal apertures or internal nostrils are two openings found at the back of the nasal passage between the nasal cavity...
socket of the shoulder joint). Another key trait is the internal nostril or choana. Most fish have two pairs of nostrils, one on either side of the head for...
pelvis (pyelo- is not to be confused with pyo-). The words infundibulum and choana are other words for funnel-shaped cavities (which medical English got from...
Anarsia choana is a moth of the family Gelechiidae. It was described by Kyu-Tek Park in 1995. It is found in Taiwan and Japan (Ryukyus). The length of...
character of this tribe is vomerine septum that completely separates the choana. Phylogeny by Gilbert et al. 2006 and Duarte et al. 2008, that showed Mazama...
lungfish and tetrapods is the divided atrium. The precise time at which the choana of tetrapods evolved is debated, with some considering early rhipidistians...
Base of skull. Inferior surface. Sagittal section of skull. Vomer Vomer Choana – Each of two openings from the nasal cavity to the throat Anatomy portal...
evolution, lungfishes have evolved internal nostrils similar to the tetrapods' choana, and a brain with certain similarities to the Lissamphibian brain (except...
posterior wall of the sphenoethmoidal recess (occurring just superior the choana). The mucous membrane receives sensory[citation needed] innervation from...
Choanal atresia is a congenital disorder where the back of the nasal passage (choana) is blocked, usually by abnormal bony or soft tissue (membranous) due to...
pterygoid fossa, the medial surface constitutes the lateral boundary of the choana or posterior aperture of the corresponding nasal cavity. Superiorly the...
vomers are fused rostrally and are extended considerably forward to the choana the single quadrate head is received completely by squamosal without paroccipital...
bacterium from the genus of Gemmobacter which has been isolated from the choana of a white stork. Parte, A.C. "Gemmobacter". LPSN. "Gemmobacter intermedius"...
a choana with a different form to that of tetrapodomorphs. The character state of the nostrils of Kenichthys demonstrates that the vertebrate choana did...
Eusthenopteron, like other tetrapodomorph fishes, had internal nostrils (or a choana), one of the defining traits of tetrapodomorphs, including tetrapods. It...
membrane ruptures and disintegrates to form an opening - the single primitive choana. The intermaxillary segment extends posteriorly to form the primary palate...
from the Greek word atretos, meaning "imperforate", and the Greek word choana, referring to a funnel or tube. Nussbaum and Wilkinson published further...
margin of the superior pharyngeal constrictor muscle. It lies lateral to the choana.[citation needed] The primary action of the muscle is to elevate and draw...
separated from one another by the choana while in Goniopholis the palatines make broad contact prior to the choana. This trait is shared by Eutretauranosuchus...
position of the secondary choana within its palate. Parts of the pterygoid bones make up the rostral margin of the choana and thus separate it from the...
contribution of the upper jaw bone, the maxilla, to the palate, in front of the choana, the inner nostril, has a depression. The brain has enlarged optic lobes...
single external nasal opening and a palatal choana. In contrast to earlier osteolepiforms, the palatal choana is elongated and the nariochoanal lamina is...
White, sticky plaques may form yellow, necrotic, cheese-like masses on the choana, tongue, or pharyngeal mucosa; there may also be moisture around the beak...
protects nerves and blood vessels.: 46 choanae The choanae (singular: choana), or internal nares (singular: internal naris), are a pair of openings in...
"Aeromicrobium choanae sp. nov., an actinobacterium isolated from the choana of a garden warbler". International Journal of Systematic and Evolutionary...
with the maxilla and premaxilla separated and an aperture—the incipient choana—on the lip in between the two bones. Kenichthys is more closely related...
from the same time period have an elongated vomer and wide and elongate choana. However, Chenoprosopus is distinguished by its more narrowly pointed snout...
duct is partially enclosed by the palatines and opens up into the internal choana towards the back where the palatines meet the pterygoid bones. In this regard...
palatal roof component of the vomer in Thrinaxodon is just dorsal to the choana, or interior nasal passages. The pterygoid bones extend in the upper jaw...
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