metazoan


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Related to metazoan: Myxozoan, Bilaterian

metazoan

(mĕt′ə-zō′ən)
n.
Any of numerous heterotrophic eukaryotic organisms of the kingdom Metazoa, characteristically having a multicellular body with cells differentiated into tissues; an animal.

met′a·zo′al, met′a·zo′an (met′a·zo′ic) adj.

metazoan

A multicellular “animal”.

metazoan

any animal of the group Metazoa, whose bodies are multicellular, as distinct from the PROTOZOANS where the bodies are unicellular. Sponges (see PARAZOAN).are the only nonprotozoan group excluded from the Metazoa. Most metazoans (except COELENTERATES) have a three-layered body structure with an outer ECTODERM, a middle MESODERM and an inner ENDODERM.
References in periodicals archive ?
There is one more set of fossils that are known from the late Ediacaran (550-543 million years) that reveal yet another aspect of the metazoan diversity before the Cambrian.
Anaerobic multicellular organisms exist in present day but their evolution in complexity is very limited compared with those achieved by aerobic metazoans. In any case it is noteworthy that the recapitulation at early embryonic stages of ancient life features like anaerobic metabolism seems to be essential for the accomplishment of normal ontogenesis even for vertebrates.
Comparative studies could also be performed with the wide range of metazoan taxa which show similar inserts, such as myriapods, proturans, and helminth worms, to find general correlations between 18S size and phenotypes (Carranza et al.
These developmental patterns allow understanding of evolutionary divergences in metazoans and of the relationships among phyla.
Blood flukes, another type of metazoan, cause schistosomiasis, a major public-health problem affecting more than 200 million people in Africa, Asia, and South America.
It should come as no surprise to learn that the authors regard robust flexibility as the source of evolvability in metazoans. Indeed, the implication is that robust flexibility is the key evolutionary innovation that triggered the diversification of metazoan phyla.
Structure, transcription, and variability of metazoan mitochondrial genome: perspectives from an unusual mitochondrial inheritance system.
In most metazoan species, mitochondrial strands are clearly asymmetric: one strand is biased in favor of A and C, and, as is the case in P.fucata martensii and P.
In relation to these fishes, 52 were parasitized by at least one species of parasitic metazoan. The following groups of metazoan parasites were found: Monogenea, parasitizing the surface and gills; Digenea, parasitizing the surface and eyes; and Nematoda present in the intestine.
Within metazoan organisms, a variety of different boundary types are present.