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“XENACOELOMORPHA”
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/ˌbaɪləˈtɪəriə/ or bilaterians, or triploblasts
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(the bilateria , are animals with…
bilateral symmetry,
i.e., they have a head (“anterior”) and a tail (“posterior”)
as well as a back (“dorsal”)
and a belly (“ventral”);
therefore they also have a ‘left side’ + a ‘right side’)
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(in contrast, ‘radially symmetrical’ animals like ‘jellyfish’ have a ‘topside’ and a ‘downside’, but no identifiable ‘front’ or ‘back’)
(the ‘bilateria’ are a major group of ‘animals’, including the majority of ‘phyla’ but not ‘sponges’, ‘cnidarians’, ‘placozoans’, and ‘ctenophores’)
(for the most part, ‘bilateral embryos’ are ‘triploblastic’, having 3 ‘germ layers’: ‘endoderm’, ‘mesoderm’, and ‘ectoderm’)
(nearly all are ‘bilaterally symmetrical’, or approximately so; the most notable exception is the ‘echinoderms’, which achieve near-radial symmetry as ‘adults’, but are bilaterally symmetrical as ‘larvae’)
(except for a few ‘phyla’ (i.e. ‘flatworms’ and ‘gnathostomulids’), bilaterians have complete digestive tracts with a separate mouth and ‘anus’)
(some ‘bilaterians’ lack ‘body cavities’ (‘acoelomates’, i.e. ‘platyhelminthes’, ‘Gastrotricha’, and ‘Gnathostomulida’), while others display primary ‘body cavities’ (deriving from the ‘blastocoel’, as ‘pseudocoel’) or ‘secondary cavities’ (that appear de novo, for example the ‘coelom’))
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*🌈✨ *TABLE OF CONTENTS* ✨🌷*
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🔥🔥🔥🔥🔥🔥*we won the war* 🔥🔥🔥🔥🔥🔥