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In invertebrate biology, an appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's body (in vertebrate biology, an example would be a vertebrate's limbs). It is a general term that covers any of the homologous body parts that may extend from a body segment. These include antennae, mouthparts (including mandibles, maxillae and maxillipeds), gills, walking legs (pereiopods), swimming legs (pleopods), sexual organs (gonopods), and parts of the tail (uropods). Typically, each body segment carries one pair of appendages. An appendage which is modified to assist in feeding is known as a (maxilliped ) or gnathopod. Appendages may become ''uniramous'', as in insects and centipedes, where each appendage comprises a single series of segments, or it may be ''biramous'', as in many crustaceans, where each appendage branches into two sections. ''Triramous'' (branching into three) appendages are also possible.There are many appendages. All arthropod appendages are variations of the same basic structure (''homologous''), and which structure is produced is controlled by "homeobox" genes. Changes to these genes have allowed scientists to produce animals (chiefly ''Drosophila melanogaster'') with modified appendages, such as legs instead of antennae. ==See also== * Appendicular skeleton ar:طرف (تشريح) ca:Pota cs:Končetina de:Extremität eo:Membro (anatomio) fr:Membre (anatomie) it:Arto he:גפה lt:Galūnė pt:Membro ru:Конечности simple:Limb fi:Raaja uk:Кінцівки ug:بەل zh:肢 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「appendage」の詳細全文を読む スポンサード リンク
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