Many terrestrial arthropods have evolved a closed respiratory system composed of spiracles, tracheae, and tracheoles to transport metabolic gasses to and from tissue. Some terrestrial woodlice have evolved pseudotrachea, a system which is also called corpus alatum, and is made up of air tubes that delivers oxygen to their hemolymph; a similar system has been found in some caterpillars. The distribution of spiracles can vary greatly among the many orders of insects, but in general each segment of the body can have no more than one pair of spiracles, each of which connects to an atrium and has a relatively large tracheal tube behind it. The tracheae are invaginations of the cuticular exoskeleton that branch (anastomose) throughout the body with diameters from only a few micrometers up to 0.8mm. The smallest tubes, tracheoles, penetrate cells and serve as sites of diffusion for water, oxygen, and carbon dioxide. Gas may be conducted through the respiratory system by means of active ventilation or passive diffusion. Unlike vertebrates, insects do not generally carry oxygen in their hemolymph; this is one of the factors that may limit their size. Animal environments are classified as either aquatic (water), terrestrial (land), or amphibious (water and land). ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - Trilobites (extinct) Subphylum Chelicerata Arachnida - Spiders, Scorpions, etc. ... The Respiratory System Among four-legged animals, the respiratory system generally includes tubes, such as the bronchi, used to carry air to the lungs, where gas exchange takes place. ... Spiracles are small openings on the surface of animals that usually lead to respiratory systems. ... Tracheole (trākē-ōl) is one of the fine branching tubes of the trachea of an insect, which penetrates the tissues to provide oxygen. ... Overview of the citric acid cycle The citric acid cycle, one of the central metabolic pathways in aerobic organisms. ... A gas is one of the four major phases of matter (after solid and liquid, and followed by plasma, that subsequently appear as a solid material is subjected to increasingly higher temperatures. ... Infraorders and Families Not necessarily a complete list Infraorders: Ligiamorpha Tylomorpha Families: Dubioniscidae Irmaosidae Pseudarmadillidae Scleropactidae Armadillidium vulgare A woodlouse, also known as a pill bug (genus Armadillidium only), armadillo bug, sow bug, slater, ball bug, or roley-poley, is a terrestrial crustacean with a rigid, segmented, calcareous exoskeleton and... Hemolymph (or haemolymph) is the blood analogue used by all arthropods and most mollusks that have an open circulatory system. ... The striking caterpillar of the Emperor Gum Moth A caterpillar is the larval form of a lepidopteran (a member of the insect order comprised of butterflies and moths). ... Scientific classification or biological classification refers to how biologists group and categorize extinct and living species of organisms. ... Orders Subclass Apterygota Symphypleona - globular springtails Subclass Archaeognatha (jumping bristletails) Subclass Dicondylia Monura - extinct Thysanura (common bristletails) Subclass Pterygota Diaphanopteroidea - extinct Palaeodictyoptera - extinct Megasecoptera - extinct Archodonata - extinct Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Blattodea (cockroaches) Mantodea (mantids) Isoptera (termites) Zoraptera Grylloblattodea Dermaptera (earwigs) Plecoptera (stoneflies) Orthoptera (grasshoppers, crickets... An endotracheal tube (ETT) is used in anaesthesia, intensive care and emergency medicine for airway management and mechanical ventilation. ... An exoskeleton, in contrast to an endoskeleton, is an external anatomical feature that supports and protects an animals body. ... This article or section does not cite its references or sources. ... Impact of a drop of water. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... == // IGOR ROCKS!!!!!!!!!!!!!!! == Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms. ... In respiratory physiology, ventilation is the rate at which gas enters or leaves the lung. ... This article or section does not cite its references or sources. ... Typical classes Petromyzontidae (lampreys) Placodermi - extinct Chondrichthyes (cartilaginous fish) Acanthodii - extinct Actinopterygii (ray-finned fish) Actinistia (coelacanths) Dipnoi (lungfish) Amphibia (amphibians) Reptilia (reptiles) Aves (birds) Mammalia (mammals) Vertebrata is a subphylum of chordates, specifically, those with backbones or spinal columns. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... Hemolymph (or haemolymph) is the blood analogue used by all arthropods and most mollusks that have an open circulatory system. ...

A tracheal tube may contain ridge-like circumferential rings of taenidia in various geometries such as loops or helices. Taenidiae are circumferential thickenings of the cuticle inside a trachea or tracheole in an insects respiratory system. ... Table of Geometry, from the 1728 Cyclopaedia. ... The term loop, in its general sense, refers to something that closes back on itself. ... A helix (pl: helices), from the Greek word έλικας/έλιξ, is a twisted shape like a spring, screw or a spiral staircase. ...

In the head, thorax, or abdomen, tracheae may also be connected to air sacs. Many insects, such as grasshoppers and bees, which actively pump the air sacs in their abdomen, are able to control the flow of air through their body. In some aquatic insects, the tracheae exchange gas through the body wall directly, in the form of a gill. Note that despite being internal, the tracheae of arthropods are shed during moulting (ecdysis). Human Head redirects here. ... Diagram of a tsetse fly, showing the head, thorax and abdomen The thorax is a division of an animals body that lies between the head and the abdomen. ... The abdomen is a part of the body. ... Families Superfamily: Tridactyloidea Cylindrachaetidae Ripipterygidae Tridactylidae Superfamily: Tetrigoidea Tetrigidae Superfamily: Eumastacoidea Chorotypidae Episactidae Eumastacidae Euschmidtiidae Mastacideidae Morabidae Proscopiidae Thericleidae Superfamily: Pneumoroidea Pneumoridae Superfamily: Pyrgomorphoidea Pyrgomorphidae Superfamily: Acridoidea Acrididae Charilaidae Dericorythidae Lathiceridae Lentulidae Lithidiidae Ommexechidae Pamphagidae Pyrgacrididae Romaleidae Tristiridae Superfamily: Tanaoceroidea Tanaoceridae Superfamily: Trigonopterygoidea Trigonopterygidae Xyronotidae Grasshoppers are herbivorous insects of... Families Andrenidae Apidae Colletidae Halictidae Megachilidae Melittidae Stenotritidae Bee collecting pollen Bees are flying insects, closely related to wasps and ants. ... gills of a Smooth Newt Gills inside of a tuna head In aquatic organisms, gills are a respiratory organ for the extraction of oxygen from water and for the excretion of carbon dioxide. ... Ecdysis is the molting of the cuticula in arthropods and related groups (Ecdysozoa). ...

References

• 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, Inc.. ISBN 0-471-15955-7. 

• Westneat, Mark W.; Betz, Oliver; Blob, Richard W.; Fezzaa, Kamel; Cooper, James W.; Lee, Wah-Keat (January 2003). "Tracheal Respiration in Insects Visualized with Synchrotron X-ray Imaging". Science 299: 558-560.