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Unformatted text preview: Phyla Porifera and Cnidaria notes Kingdom Animalia : Animals are eukaryotic, multicellular, ingestive-feeding heterotrophs. Each phylum of the animal kingdom represents a unique body plan. Some phyla are also subdivided into classes. Phylum Porifera (sponges)- asymmetrical bodies (no symmetry or pattern)- lack distinct tissues and organs- loose assemblage of cells, lacks true tissues- unique cells choanocytes (collar cells), flagellated cells that draw water in and filter food particles- filter-feeding heterotrophs- have no photosynthetic pigments- Morphology: o Epithelial layer forms outer wall. o The walls are lined with choanocytes, amoebocytes, spicules, and mesenchyme. Amoebocytes are mobile cells that can be used for: Digestion Ability to differentiate other cell types Secrete calcareous spicules, siliceous spiculues, or proteinaceous spongin fibers Spicules are crystalline skeletal structures that help reinforce the wall. Choanocytes are surrounded by a collar of microvilli (traps food particles) and have a flagellum (draws in water through pores to the spongocoel); they are flagellated cells that draw in water and filter food particles. Pores formed by porocytes Spongocoel is the inside of the sponge (central cavity) Food from microvilli moves toward base of cell into a food vacuole Food vacuole pass to amoeboid cells ( intracellular digestion occurs) Filtered water exits through large hole in the end of the sponge called osculum Mesenchyme is a gelatinous matrix- Sponge Reproduction: Asexually and sexually o Most species of sponges are monoecious or hermaphroditic (have both male and female sex organs) but produce eggs and sperm at different times....
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This note was uploaded on 04/08/2008 for the course BIO 1106 taught by Professor Youngblood,aaron during the Spring '08 term at Baylor.
- Spring '08