Any of some 2,000 species (chordate subphylum Tunicata, or Urochordata) of small marine invertebrates that are abundant worldwide. Tunicates are either sessile (permanently attached), free-swimming, or planktonic (floating). The name tunicate derives from a secreted protective covering (the tunic) containing cellulose. Floating species often form colonies that may be 13 ft (4 m) long. Some free-swimming species are too small to see. Adults filter feed on microorganisms. Sessile forms growing on ships' hulls may be a nuisance, but some species are pharmaceutically useful. Seealso sea squirt.
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Evolution of developmental roles of Pax2/ 5/ 8 paralogs after independent duplication in urochordate and vertebrate lineages.(Research article)
Aug 22, 2008; Authors: Susan Bassham (equal contributor) ; Cristian Cañestro (equal contributor) ; John H Postlethwait (corresponding...
Endostyle cell recruitment as a frame of reference for development and growth in the urochordate Oikopleura dioica.(Report)
Dec 01, 2007; Introduction Several approaches are used to study development and growth. At the subcellular scale, molecular studies reveal...