Deuterostomia


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Related to Deuterostomia: Bilateria, Protostomia

Deuterostomia

[‚düd·ə·rō′stō·mē·ə]
(zoology)
A division of the animal kingdom which includes the phyla Echinodermata, Chaetognatha, Hemichordata, and Chordata.

Deuterostomia

 

an inclusive term comprising animals of the three phyla Hemichordata, Echinodermata, and Chordata. The term “Deuterostomia” was introduced into the system of animal classification by the German zoologist K. Grobben in 1908. In contrast to the Protostomia, deuterostomes form a new mouth opening during their embryonic development that is independent of the protostoma, or blastopore (the latter usually becoming the anus). Deuterostomia have a secondary body cavity, or coelom, which develops from an out-pouching of the intestine. The endoskeleton is of mesodermal origin. The nervous system takes the form of an ectodermal plate with in-pouchings under the skin. The biochemistry of muscle contraction in Deuterostomia is characterized by the formation of creatine phosphate. The phyla Chaetognatha and Pogonophora are now also included among the Deuterostomia.

A. V. IVANOV

References in periodicals archive ?
It may furthermore indicate that the tubular gut evolved independently in Protostomia and Deuterostomia, but the uncertainty about the early evolution of the deuterostomes (see below) makes this difficult to ascertain.
Further, current data indicate that the p63 gene antedated the divergence of the Ecdysozoa, Lophotrochozoa, and Deuterostomia (Aguinaldo et al.
The principal difference in cellular mechanisms of heart-muscle growth between Deuterostomia and Proterostomia may be accounted for by different origin and development of cardiogenic mesoderm in these two main phylogenic taxa.
the chaetognaths have been shown not to be in the Deuterostomia despite the fact that their blastopore is retained to form an anus (34, 35), and some potentially important characters - for example, the similar setae of annelids and brachiopods - are occasionally overlooked.