What is Trachea?
{{otheruses}} {{no sources }} The '''trachea''', or '''windpipe''', is the [[bone|bony]] tube that connects the [[nose]] and [[mouth]] to the [[lung]]s, and is an important part of the [[vertebrate]] [[respiratory system]]. [[File:Blausen_0865_TracheaAnatomy.png|thumb|250px|Anatomy of a human trachea]] In [[mammal|mammals]], the trachea begins at the lower part of the [[larynx]] and continues to the lungs. There it branches into the right and left [[bronchi]]. [[Inflammation]] of the trachea can lead to other conditions, such as [[tracheitis]], which is the inflammation of the linings of the trachea. == Invertebrate trachea == [[File:Tracheal system of dissected cockroach.tif|thumb|Tracheal system of dissected [[cockroach]]. The largest tracheae run across the width of the body of the cockroach and are horizontal in this image. [[Scale (ratio)|Scale bar]], 2 mm]] [[File:Cockroach tracheae supplying crop.tiff|thumb|The tracheal system branches into progressively smaller tubes, here supplying the [[Crop (anatomy)|crop]] of the cockroach. Scale bar, 2 mm]] The '''invertebrate trachea''' refers to the open [[respiratory system]] of [[terrestrial animal|terrestrial]] [[arthropod]]s. It consists of [[spiracles]], tracheae, and [[tracheole]]s that take [[metabolism|metabolic]] gases to and from tissues.<ref>Wasserthal, Lutz T. 1998. Chapter 25: The open hemolymph system of Holometabola and its relation to the tracheal space. In ''Microscopic anatomy of invertebrates''. Wiley-Liss. {{ISBN|0-471-15955-7}}</ref> The distribution of spiracles varies, but in general each segment of the body has only one pair of spiracles, each of which connects to an [[Atrium (invertebrates)|atrium]] and has a relatively large tracheal tube behind it. The smallest tubes, tracheoles, penetrate cells and [[diffusion|diffuse]] water, [[oxygen]], and [[carbon dioxide]]. [[Gas]] may be moved actively or by passive diffusion. Unlike [[vertebrates]], [[Insect|insects]] do not generally carry oxygen in their [[hemolymph|haemolymph]].<ref>{{c