BIOL 1030 Chapter Notes - Chapter 33: Gastrovascular Cavity, Rotifer, Lophophore

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1030
• Professor: Scott Kevin

Document Summary

Invertebrates inhabit nearly all environments on earth, from the scalding water of deep-sea hydrothermal vents to the rocky, frozen ground of antarctica. In some groups of sponges, these fibers are sharp spicules of calcium carbonate or silica: other sponges produce more flexible fibers from a collagen protein called spongin. The lophophorate phyla: ectoprocts, phoronids, and brachiopods are coelomates with ciliated tentacles around their mouths: bilaterians in three phyla ectoprocta, phoronida, and. In addition to the lophophore, these three phyla share a u-shaped digestive tract and the absence of a head: these may be adaptations to a sessile existence. In contrast to flatworms, which lack a body cavity, and rotifers, which have a pseudocoelom, lophophorates have true coeloms completely lined with mesoderm: ectoprocts are colonial animals that superficially resemble plants. In these species, the radula is modified to bore holes in the shells of other organisms or to tear apart tough animal tissues.