Respiration organ
Encyclopedia : R : RE : RES : Respiration organ
Breathing / Respiration organs are used by most, or all, animals to exchange the gasses necessary for their life functions, known as respiration. These organs come in many forms, some of them apparently having independently evolved:
- skin -- some aquatic, or small terrestrial (some of the smallest spiders and mites, for example), animals can respirate simply by exchanging gas through the surface of their body
- gill -- many aquatic, and a few smaller terrestrial, animals use gills to breath. Yes, even land animals can do this, as with isopods like the pill bugs you probably can find living under rocks in your yard. Gills are simply layers of tissue adapted specifically to gas exchange.
- book lung -- Some spiders, scorpions, and other arthropods still use primitive book lungs, essentially gills adapted for land use, in their respiration. These are simply tissue with many wrinkles to increase their surface area.
- Labyrinth organ -- A secondary breathing organ specific to the labyrinth fish, essentially an enclosed maze of tissue, evolved from a niche in their gill structure.
- trachea -- tubes evolved by many arthropods, possibly from book lungs, which simply lead directly into their bodies through holes called spicules, where their internal organs generally absorb their own air. These can be very primitive, as with some spiders, or more complex, ending with specialized air sacs, as with many insects.
- lung -- Complex, enclosed respiratory organs evolved by some kinds of bony fishes, and through them various terrestrial descendants, up to and including human beings.
From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.
All text is available under the terms of the GNU Free Documentation License See Wikipedia Copyrights for details.