Name Period Chapter 18: The Evolution of Invertebrate Diversity Guided Reading Activities Big idea: Animal evolution and diversity Answer the following questions as you read modules 18.1 18.4: 1. The eating of food by animals is known as. 2. Briefly contrast how fungi get their nutrients with how a human does. 3. You discover a new organism at a research station outside Acadia National Park. You observe that the organism produces haploid gametes by way of mitosis. Is this new organism an animal? Briefly explain your answer either way. 4. What is meant when scientists refer to the Cambrian explosion? 5. True or false: Vertebrates largely outnumber invertebrates. If false, make it a correct statement. 6. In Greek, protos means first, deuteron means second, and stoma means mouth. Use this information to explain why the terms protostome and deuterostome are accurate descriptors. 7. Complete the following table, which compares radial symmetry to bilateral symmetry. Bilateral symmetry Radial symmetry of an organism that displays this type of symmetry 114 Copyright 2015 Pearson Education, Inc. REEC7833_01_C18_PRF.indd 114
8. Assume that you are studying a group of organisms with true tissues. Which of the types of organisms in Figure 18.4 on page 369 of your textbook would be considered the outgroup? 9. At which branch point did humans (chordates) diverge from cnidarians? (Hint: Identify the derived character.) 10. Which of the following types of animals does not have radial symmetry? a. Molluscs b. Arthropods c. Nematodes d. All of the above have radial symmetry. Big idea: Invertebrate diversity Answer the following questions as you read modules 18.5 18.16: 1. True or false: The cells of sponges are only loosely associated with each other, which is why they are not considered true tissues. If false, make it a correct statement. 2. The are the cells of sponges that closely resemble the choanoflagellates. 3. Your bath sponge contains what protein secreted by amoebocytes? 4. Cnidarians are characterized by and. 5. Compare the two body forms associated with the radial cnidarians. 6. List two similarities that flatworms have with us when comparing body plans. List a difference. Copyright 2015 Pearson Education, Inc. 115 REEC7833_01_C18_PRF.indd 115
7. Complete the following table, which compares the different types of flatworms. Free-living flatworms Flukes Tapeworms 8. Explain the advantages of having a complete digestive tract. 9. Nematodes and humans both have symmetry. 10. Which of the following is involved in a snail moving through your garden? a. Mantle b. Foot c. Visceral mass d. Radula 11. Complete the following table, which compares the three major groups of molluscs. Gastropods Bivalves Cephalopods 12. True or false: Annelids are lophotrochozoans that display body segmentation. If false, make it a correct statement. 13. Briefly compare open circulatory systems with closed circulatory systems. 116 Copyright 2015 Pearson Education, Inc. REEC7833_01_C18_PRF.indd 116
14. Complete the following table, which describes the three major groups of annelids. Earthworms Polychaetes Leeches 15. Arthropods are an extremely successful group of animals in terms of population, diversity, and distribution. In general, what three features are attributed to that success? 16. Complete the following table, which compares three of the four major groups of arthropods. Chelicerates Millipedes and centipedes Crustaceans 17. What features about the reproduction of many insects allow them to adapt to their environment quickly? 18. An insect has a mutation occur in a homeotic gene in the abdomen segment. Briefly explain why this is not necessarily bad for the other segments. 19. Insects are the only invertebrates that can fly. However, their wings do not develop from any of the legs; rather they develop from the. 20. What experimental evidence led scientists to believe what accounts for the great diversity associated with arthropods? Copyright 2015 Pearson Education, Inc. 117 REEC7833_01_C18_PRF.indd 117
21. True or false: Echinoderms display radial symmetry as an adult, but they display bilateral symmetry in their larval stage. If false, make it a correct statement. 22. What is the function of the water vascular system that is unique to echinoderms? 23. The four distinguishing features of the phylum Chordata include: 24. True or false: According to molecular evidence, lancelets are the closest nonvertebrate relative of vertebrates. If false, make it a correct statement. 25. List three services provided for us by invertebrates and the way in which each one is threatened by human activities. Connecting the Big Ideas Use your knowledge of the information contained within this chapter s Big Ideas to answer this question. How do the skeletons of chordates compare to echinoderms? 118 Copyright 2015 Pearson Education, Inc. REEC7833_01_C18_PRF.indd 118