Kingdom Animalia: Porifera, Cnidaria, Platyhelminthes, Nematoda Exam Questions and Answers

Phylum Porifera - ANSWER simple, sessile (permanently attached to one location) sponges; no tissues, organs, mouth or digestive cavity; filter feeders: flagellated collar cells line the large internal cavity and draw water into the sponge (food particles are strained out of the water current by the collar cells which pass food to other sponge cells); acolemate (no colon); no symmetry; most are marine Phylum Cnidaria - ANSWER class hydrozoa, class scyphozoa, class anthozoa; jellyfish, sea anemones, hydra, obelia, portugese man-o-war, coral; mostly marine, two body forms (free swimming medusa, sessile polyp); acolemate; radial symmetry; body is composed of 2 tissue layers and a gastrovascular cavity with no anus; cnidocytes or stinging cells that are on the tentacles surrounding the mouth Radial Symmetry - ANSWER body is arranged around a center point (like a pie) and several planes passing through its long axis Phylum Platyhelminthes - ANSWER class turbellaria, class cestoda, class trematoda; flat worms, free-living turbellarians, parasitic flukes, tapeworms; most marine but some freshwater; acolemates (no colon); digestive gut to present with no anus; bilateral symmetry; first to have cephalization (development of sensory and nervous tissue into head end of body); three tissue layers - endoderm, mesoderm, ectoderm Bilateral Symmetry - ANSWER only one plane can divide the body into mirror halves Phylum Nematoda - ANSWER roundworms, both free living and parasitic; first to have a gut along with a mouth adn anus; pseudocolemate wall and digestive tract; bilateral symmetry; three tissue layers Pseudocolemate - ANSWER body cavity is only partially lined with mesodermal tissue that separates body Phylum Porifera: Sponges - ANSWER sponges are unusual animals found mostly in oceans, although there are some freshwater; consist of few cell types of various functions loosely organized throughout the asymmetrical body of the sponge Water is moved through the - ANSWER sponge by currents created by active flagellated cells that line the interior channels leading into the sponge from the pores Strong protein fibers, or sporangia - ANSWER compose the sponge skeleton Phylum Cnidaria: Cnidarians are mostly marine - ANSWER animals. General structure includes a sac like body with one opening (mouth) that is surrounded by tentacles. tentacles are armed with cnidocytes (stinging cells) that paralyze organisms; occur in two body forms the polyp and medusa; in addition to tissues, cnidarians are the first animals to have true nerve cells that are spread as a loose simple net throughout the body Kingdom Animalia: Phylum Cnidaria: Class Hydrozoa: Hydra - ANSWER the freshwater hydra represents the polyp body form of the cnidarians Kingdom Animalia: Phylum Cnidaria: Class Hydrozoa: Obelia - ANSWER these cnidarians are mostly marine and live in polyp colonies; can also be found in the medusa body form Kingdom Animalia: Phylum Cnidaria: Class Scyphozoa: Jellyfish - ANSWER marine animals; represent the medusa body form of cnidarians; the name comes from its large quantity of mesoglea, the jelly like substance that separates cnidarians two tissues Kingdom Animalia: Phylum Cnidaria: Class Anthozoa: Sea Anemones - ANSWER of the polyp form and resemble an enlarged hydra; contract when disturbed by pulling in their tentacles and shortening their bodies; they are common in tide pools Kingdom Animalia: Phylum Cnidaria: Class Anthozoa: Coral - ANSWER secrete calcium carbonate (the white stony substance of coral); builds up around the animals and serves as a protective exoskeleton Kingdom Animalia: Phylum Platyhelminthes: flatworms - ANSWER known as flatworms because of their riboon-like appearance; first in the animal kingdom to have a definite head region containing sensory organs; possess all three germ layers Kingdom Animalia: Phylum Platyhelminthes: Class Turbellaria: Planarians - ANSWER freshwater, free-living (non parasitic) flatworms; their lower body surface is covered with cilia that aid in locomotion Kingdom Animalia: Phylum Platyhelminthes: Class Cestoda: Tapeworms - ANSWER intestinal parasites; the head is located at the narrow end of the worm; body segments-called proglottids, continually grow from the neck region and increase in size as they mature; most mature proglottids are furthest from the head Kingdom Animalia: Phylum Platyhelminthes: Class Trematoda: Flukes - ANSWER parasitic; suckers to attach to host; invertebrate and vertebrate hosts Kingdom Animalia: phylum Nematoda: roundworms - ANSWER called roundworms because of their slender circular bodies; extremely numerous in every kind of terrestrial and aquatic habitat, many being microscopic; have a complete digestive canal with a mouth and anus Kingdom Animalia: Phylum Nematoda: Ascaris - ANSWER nematode is an intestinal parasite found in pigs and humans; sexes can be determined by the larger size of the female and the hooked end of the tail on the male What kind of symmetry do sponges have - ANSWER bilateral