Outline Sponges, Phylum Porifera Invertebrate Animals Outline Sponges, Phylum Porifera 28 May 2015 Invertebrate-1.ppt

Animal Life Four critical processes Easy for 1-few cells Obtain energy and material Ingest, digest, absorb Obtain oxygen Dispose of nitrogenous waste NH3, urea, uric acid Dispose of CO2 Easy for 1-few cells 28 May 2015 Invertebrate-1.ppt

Animal Life Harder for multicellular organisms Large multicellular organisms require Internal circulation Coordination, information transfer Structural maintenance Movement Maintenance of homeostatic internal environment 28 May 2015 Invertebrate-1.ppt

Animal Life We will study 9 Phyla in order of increasing complexity. 28 May 2015 Invertebrate-1.ppt

Animal Life Outline for each Phylum: Name and etymology General characters Body plan and example Gut, symmetry, etc. Cell and tissue organization Special, unique “distinguishing” characters Where & how they live 28 May 2015 Invertebrate-1.ppt

Animal Life Outline for each Phylum (continued): Special concerns of a multicellular animal Food, gas exchange, waste removal Circulation, Coordination, Structural support, Movement, Maintenance of homeostasis—water balance. Reproduction Classes (and Orders ?) Distinguishing the Classes 28 May 2015 Invertebrate-1.ppt

Animal Life Geologic Time Scale (Table 25.1, page 527) Names of Eras in order Names of Periods and Epochs, associated with Era 28 May 2015 Invertebrate-1.ppt

Animal Life Early fossil record of animals Simplest animals Sponges Cnidarians 28 May 2015 Invertebrate-1.ppt

Phylum Porifera Phylum Porifera (Calcarea + Silicea) “pore bearers” No symmetry; may resemble radial symmetry Marine, freshwater Cells Four kinds: “epidermal,” amoebocytes, porocytes, choanocytes 28 May 2015 Invertebrate-1.ppt

Phylum Porifera Unique characters Choanocytes (collar cells) Cell body, flagellum, collar Feeding cells Shared with choanoflagellates Are sponges animals ? Spicules Spongocoel & osculum 28 May 2015 Invertebrate-1.ppt

Phylum Porifera Special concerns Water flow Food O2 and CO2 exchange Waste removal Water flow 28 May 2015 Invertebrate-1.ppt

Phylum Porifera Special concerns: Water flow for circulation Little coordination Chemical communication, no nerve cells Skeletons of CaCO3, SiO2, spongin Little movement, no muscle cells Each cell maintains itself 28 May 2015 Invertebrate-1.ppt

Phylum Porifera Reproduction Classification uncertain (polyphyletic ?) Sequential hermaphrodites Asexual Classification uncertain (polyphyletic ?) Classes based on nature of skeleton Spicules of CaCO3 Spongin Both Spicules of SiO2 28 May 2015 Invertebrate-1.ppt