Biol 211 (2) Chapter 34 Lophotrochozoans

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Biol 211 (2) Chapter 34 Lophotrochozoans

Supplemental Instruction Biology 211 (2) Week 5 Chapter 34: Lophotochozoans 1. What is the lophophore function? Trochophore function? 1. Lophophore: Feeding, respiration; Trochophore: Movement, feeding! Platyhelminthes (Flatworms) Ceolom type Aceolomate Symmetry Bilateral Reproduction Sexual; Hermaphroditic; Sometimes asexual Feeding System Gastrovascular cavity! Incomplete Digestive System Gastrula (Yes or No) Yes Tissue (Yes or No) Yes Protostomes or Deuterostomes Protostomes Lophophore/Trochophore No Triploblasty or Diploblasty Triploblastic Segmented (Yes/No) No Ecosystem Marine, freshwater, damp habitats One Free-living Class Turbellaria (Planarians) Three Parasitic Class Monogenea, Trematoda (Flukes), Cestoda (Tapeworms) 1. Platyhelminthes intake prey through the mouth by a muscular protractible_________. 1. Pharynx 2. What is a major difference between free-living and parasitic Platyhelminthes? 1. Reproductive effort is higher in the body plan of the parasitic Platyhelminthes, while digestive efforts are higher in the free-living. 3. Name at least four characteristics of parasitic Platyhelminthes. Supplemental Instruction 4. Do tapeworms have a digestive tract? 1. No, absorb nutrients that are pre-digested by host Annalida Ceolom type Ceolomate Symmetry Bilateral Reproduction Sexual; Hermaphroditic; sometimes asexual Feeding System Complete Digestive System Gastrula (Yes or No) Yes Tissue (Yes or No) Yes Protostomes or Deuterostomes Protostomes Lophophore/Trochophore Yes Triploblasty or Diploblasty Triploblastic Segmented (Yes/No) Yes Ecosystem Marine, freshwater, damp habitats Three Groups Polychaeta (mostly marine), Oligochaeta (Earthworms), Hirudinea (Leeches) 1. What are two advantages of segmentation? 1. Repetition of components provides backup (able to grow back when part is cut off) 2. Permits specialization 2. What is the function of parapodia in Polychaetes? 1. Parapodia function in both movement and gas exchange 3. What are some reasons that earthworms are ecologically important? 1. Digest organic matter; tunnels left behind earthworms help aerate the soil Mollusca Ceolom type Ceolomate Symmetry Bilateral Reproduction Sexual; Some Hermaphroditic; some asexual Feeding System Complete digestive System Gastrula (Yes or No) Yes Tissue (Yes or No) Yes Protostomes or Deuterostomes Protostomes Lophophore/Trochophore Yes Triploblasty or Diploblasty Triploblastic Supplemental Instruction Mollusca Segmented (Yes/No) No Ecosystem Most marine, some freshwater and terrestrial Two Classes with Radula (Examples) Gastropoda (Snails/slugs), Cephalopoda (Squids, Octopi) One Class w/o Radula (Examples) Bivalvia (Clams, Mussels) 1. For the Molluscan body plan, what five parts doe they all have? 1. Foot, mantle, shell, visceral mass, gill 2. Does the phylum Mollusca have an open or closed circulatory system? 1. Depends on the energy needs of the clade. If they need a lot of energy, then closed. 3. What is a radula? 1. Used for feeding to cut or scrape food 4. Many species of freshwater mussels have a larval stage called ______ that need a host. 1. Glochidium.

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Review Sheet for Lecture 15: Life in the Benthic Realm
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This article was downloaded by: [T&F Internal Users], [Carol Wakefield] On: 26 October 2011, At: 04:20 Publisher: Taylor & Francis Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Toxicological & Environmental Chemistry Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/gtec20 Effect of pH, iron and aluminum on survival of early life history stages of the endangered freshwater pearl mussel, Margaritifera margaritifera J. Taskinen a , P. Berg a , M. Saarinen-Valta a , S. Välilä a , E. Mäenpää b , K. Myllynen b & J. Pakkala b a Department of Biological and Environmental Science, University of Jyväskylä, PO Box 35, FI-40014 Jyväskylä, Finland b South Ostrobothnian Centre for Economic Development, Transport and Environment, PO Box 77, FI-67101, Kokkola, Finland Available online: 16 Aug 2011 To cite this article: J. Taskinen, P. Berg, M. Saarinen-Valta, S. Välilä, E. Mäenpää, K. Myllynen & J. Pakkala (2011): Effect of pH, iron and aluminum on survival of early life history stages of the endangered freshwater pearl mussel, Margaritifera margaritifera , Toxicological & Environmental Chemistry, 93:9, 1764-1777 To link to this article: http://dx.doi.org/10.1080/02772248.2011.610798 PLEASE SCROLL DOWN FOR ARTICLE Full terms and conditions of use: http://www.tandfonline.com/page/terms-and- conditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date.
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• Every Major Animal Phylum That Exists on Earth Today, As Well As A
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