FACTOID # 14: North Carolina has a larger Native American population than North Dakota, South Dakota and Montana combined.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Respiratory tract

In humans the respiratory tract is the part of the anatomy that has to do with the process of respiration or breathing. Anatomical drawing of the human muscles from the Encyclopédie. ... For the play Breath by Samuel Beckett, see Breath (play). ...


The respiratory tract is divided into 3 segments:

The respiratory tract is a common site for infections. Upper respiratory tract infections are probably the most common infections in the world. The Upper respiratory tract refers to the the following parts of the respiratory system: nose and nasal passages paranasal sinuses throat or pharynx Upper respiratory tract infections are among the most common infections in the world. ... For the article about nose in humans, see human nose Human nose in profile Elephants have prehensile noses Dogs have very sensitive noses Anatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration. ... The paranasal sinuses are eight (four pairs) air-filled spaces, or sinuses, within the bones of the skull and face. ... Look up Throat in Wiktionary, the free dictionary. ... The pharynx (plural: pharynges) is the part of the neck and throat situated immediately posterior to the mouth and nasal cavity, and cranial, or superior, to the esophagus, larynx, and trachea. ... The larynx (IPA læɹɪŋks) is an organ in the neck of mammals involved in protection of the trachea and sound production. ... Voicebox redirects here. ... The trachea, or windpipe, is a tube that has a inner diameter of about 12mm and a length of about 10-12cm. ... A bronchus (plural bronchi, adjective bronchial) is a caliber of airway in the respiratory tract that conducts air into the lungs. ... The bronchioles are the first airway branches that no longer contain cartilage. ... Respiratory system The lungs flank the heart and great vessels in the chest cavity. ... The bronchioles are the first airway branches that no longer contain cartilage. ... Alveolar ducts are the tiny end tubules of the branching airways that fill the lungs. ... Detailed drawing of the alveoli from Grays Anatomy, 1918 - Schematic longitudinal section of a primary lobule of the lung (anatomical unit); r. ... The alveoli (singular:alveolus), tiny hollow sacs which are continuous with the airways, are the sites of gas exchange with the blood. ... Upper respiratory infections, commonly referred to the acronym URI, is the illness caused by an acute infection which involves the upper respiratory tract: nose, sinuses, pharynx, larynx, or bronchi. ...


Most of the respiratory tract exists merely as a piping system for air to travel in the lungs; alveoli are the only part of the lung that exchanges oxygen and carbon dioxide with the blood. The alveoli (singular:alveolus), tiny hollow sacs which are continuous with the airways, are the sites of gas exchange with the blood. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Standard atomic weight 15. ... Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. ... Human blood smear: a - erythrocytes; b - neutrophil; c - eosinophil; d - lymphocyte. ...


Moving down the respiratory tract starting at the trachea, the tubes get smaller and divide more and more. There are estimated to be about 20 to 23 divisions, ending up at an alveolus.


Even though the cross-sectional area of each bronchus or bronchiole is smaller, because there are so many, the total surface area is larger. This means there is less resistance at the terminal bronchioles. (Most resistance is around the 3-4 division from the trachea due to turbulence.)


General histology

The respiratory tract is covered in an epithelium, the type of which varies down the tract. There are glands and mucus produced by goblet cells in parts, as well as smooth muscle, elastin or cartilage. Types of epithelium This article discusses the epithelium as it relates to animal anatomy. ... A gland is an organ in an animals body that synthesizes a substance for release such as hormones, often into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). ... Mucus is a slippery secretion of the lining of various membranes in the body (mucous membranes). ... Goblet cells are glandular simple columnar epithelial cells whose sole function is to secrete mucus. ... Cultured Smooth muscle of the aorta. ... Elastin, also known as elasticin, is a protein in connective tissue that is elastic and allows skin to return to its original position when it is poked or pinched. ... Cartilage is a type of dense connective tissue. ...


Most of the epithelium (from the nose to the bronchi) is covered in pseudostratified columnar ciliated epithelial cells, commonly called respiratory epithelium. The cilia beat in one direction, moving mucus towards the throat where it is swallowed. Moving down the bronchioles, the cells get more cuboidal in shape but are still ciliated. cross-section of two cilia, showing 9+2 structure A cilium (plural cilia) is a fine projection from a eukaryotic cell that constantly beats in one direction. ... In zootomy, epithelium is a tissue composed of a layer of cells. ... Respiratory epithelium is another name for ciliated pseudostratified columnar epithelium with goblet cells. ...


Cartilage is present until the small bronchi. In the trachea they are C-shaped rings, whereas in the bronchi they are interspersed plates.


Glands are abundant in the upper respiratory tract, but there are fewer lower down and they are absent from the bronchioles onwards. The same goes for goblet cells, although there are scattered ones in the first bronchioles.


Smooth muscle starts in the trachea, where it joins the C-shaped rings of cartilage. It continues down the brochi and bronchioles which it completely encircles.


Instead of hard cartilage, the bronchi and brochioles have a lot of elastic tissue.


doody!


Reference

  • Syllabus: Infectious Diseases see Respiratory Tract Infections by Neal Chamberlain, PhD. Kirksville College of Osteopathic Medicine, Missouri, USA

See also


  Results from FactBites:
 
Respiratory tract - Wikipedia, the free encyclopedia (418 words)
Lungs: respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli
Most of the respiratory tract exists merely as a piping system for air to travel in the lungs; alveoli are the only part of the lung that exchanges oxygen and carbon dioxide with the blood.
The respiratory tract is covered in an epithelium, the type of which varies down the tract.
Upper respiratory tract infection - Wikipedia, the free encyclopedia (341 words)
Upper respiratory tract infection, also popularly known as either the acronym URTI or URI, is the disease characterised by an acute infection which involves the upper respiratory tract: nose, sinuses, pharynx, or larynx.
Otitis media is an infection of the ear (which is part of the auditory system) often associated with upper respiratory infections.
Influenza is a more systemic illness which can also involve the upper respiratory tract and should be recognized as distinct from other causes of URI.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m