Molluscs. Development of the coelom In the precambrian era, the most complex animals in the seas were acoelomate With time, some animals developed a more.
Phylum Mollusca
Molluscs. Introduction Introduction. One of the largest animal phyla after the arthropods. 50,000 ‑ 100,000 living species, 35,000 extinct. Mollusca means.
Invertebrate Phylum's. Invertebrate Basics: Animals with no backbones Multi-cellular, cells have no cell walls Most can move Most have symmetry, meaning.
Phylum: Porifera asymmetrical egg turns to free swimming larva that attaches to rock and undergoes metamorphosis into adult the body wall consists of two.
