Nostril

Nostril
"Nares" redirects here. For information about the nostrils of a bird, see Beak#Nares. For other uses, see Nares (disambiguation).
Human nostrils
Raccoon nostrils

A nostril (or naris, pl. nares) is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation. Fish do not breathe through their noses, but they do have two small holes used for smelling which may be called nostrils.

The Procellariiformes are distinguished from other birds by having tubular extensions of their nostrils.

In humans, the nasal cycle is the normal ultradian cycle of each nostril's blood vessels becoming engorged in swelling, then shrinking.

The nostrils are separated by the septum. The septum can sometimes be deviated, causing one nostril to appear larger than the other. In such an event, the two nostrils are no longer separated and form a single larger external opening.[1]

Humans have two external nostrils with two additional nostrils inside the head. These internal nostrils are called "choanae" and each contain approximately 1000 strands of nasal hair. They also connect the nose to the throat aiding in respiration. Scientists believe they migrated back inside as evidenced by the discovery of "Kenichthys campbelli", a 395 million-year-old fossilized fish which shows this migration in progress. It has two nostrils between its front teeth, similar to human embryos at an early stage. If these fail to join up it causes a cleft palate.[2]


It is possible for humans to smell different olfactory inputs in the two nostrils and experience a perceptual rivalry akin to that of binocular rivalry when there are two different inputs to the two eyes.[3]

See also

References

  1. ^ "Cocaine destroyed my nose, admits 'EastEnders' star", The Independent, June 6, 2000.
  2. ^ Lloyd, John; Mitchinson, John (December 2, 2008 (2008-12-02)). The Book of General Ignorance. London: Faber and Faber Ltd.. pp. 2, 299. ISBN 978-0-571-24139-2. http://books.google.com/books?id=4AhXPgAACAAJ. Retrieved July 16, 2011. 
  3. ^ Zhou W, Chen D. (2009). Binaral rivalry between the nostrils and in the cortex. Curr Biol. 19(18):1561-5. doi:10.1016/j.cub.2009.07.052 PMID 19699095

External links

  • "nares" at Dorland's Medical Dictionary
v · d · eHead and neck, upper RT: Nose (TA A06.1, TH H3.05.01, GA 10.992)
External nose
Nasal cavity
Openings
Lateral wall
Medial wall
Paranasal sinuses
Naso-pharynx

M: RES

anat(n, x, l, c)/phys/devp

noco(c, p)/cong/tumr, sysi/epon, injr

proc, drug(R1/2/3/5/6/7)

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Look at other dictionaries:

  • Nostril — Piercing Lage Nasenflügel Schmuck Ball Closure Ring, Bar Closour Ring, Circular Barbell, Labret Stud, Curved Nose Studs, Nose Bones Hinweis zum Schmuck …   Deutsch Wikipedia

  • Nostril — Nos tril, n. [OE. nosethril, nosethirl, AS. nos[thorn]yrl; nos for nosu nose + [thorn]yrel opening, hole, from [thorn]yrel pierced, for [thorn]yrhel, fr. purh through. [root]261. See {Nose}, and {Through}, and cf. {Thrill}.] [1913 Webster] 1.… …   The Collaborative International Dictionary of English

  • nostril — (n.) O.E. nosþyrl, nosðirl, lit. the hole of the nose, from nosu nose (see NOSE (Cf. nose) (n.)) + þyrel hole (see THRILL (Cf. thrill) (v.)) …   Etymology dictionary

  • nostril — ► NOUN ▪ either of two external openings of the nose that admit air to the lungs and smells to the olfactory nerves. ORIGIN Old English, «nose hole» …   English terms dictionary

  • nostril — [näs′trəl] n. [ME nosethirl < OE nosthyrl < nos, for nosu, the nose + thyrel, a hole < thurh, through: see NOSE & THROUGH] 1. either of the external openings of the nose 2. the fleshy wall on either side of the nose [with flaring… …   English World dictionary

  • nostril — noun VERB + NOSTRIL ▪ fill ▪ The stench of the cellar filled my nostrils. NOSTRIL + VERB ▪ flare NOSTRIL + NOUN ▪ hair …   Collocations dictionary

  • nostril — UK [ˈnɒstrəl] / US [ˈnɑstrəl] noun [countable] Word forms nostril : singular nostril plural nostrils one of the two holes at the end of your nose …   English dictionary

  • nostril — [OE] Etymologically, a nostril is a ‘nosehole’. Its Old English ancestor was nosthyrl, a compound formed from nosu ‘nose’ and thyrl ‘hole’. This was a derivative of thurh ‘through’, and still survives as thirl, a dialectal word for ‘hole’. =>… …   The Hutchinson dictionary of word origins

  • nostril — [OE] Etymologically, a nostril is a ‘nosehole’. Its Old English ancestor was nosthyrl, a compound formed from nosu ‘nose’ and thyrl ‘hole’. This was a derivative of thurh ‘through’, and still survives as thirl, a dialectal word for ‘hole’. Cf.⇒… …   Word origins

  • Nostril Piercing — Lage Nasenflügel Schmuck Ball Closure Ring, Bar Closour Ring, Circular Barbell, Labret Stud, Curved Nose Studs, Nose Bones Hinweis zum Schmuck …   Deutsch Wikipedia

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