1. in Most Cnidarians, Fertilized Eggs Give Rise to Free-Swimming, Multicellular, Ciliated

Chapter 32 Name ______

1. In most Cnidarians, fertilized eggs give rise to free-swimming, multicellular, ciliated larvae, known as P______.

2. An animal discovered by scientists is clearly multicellular showing what appears to be radial symmetry but does not have cells organized into tissues. This animal is placed in the group P______.

3. New rRNA phylogenies differ most from the traditional phylogenies in the P______branch of the family tree.

4. A major evolutionary innovation found in C______is the internal extracellular digestion of food.

5. Cnidarians characteristically possess specialized cells called cnidocytes, which contain a N______, a harpoon used to attack prey.

6. Many A______which live in shallow waters harbor symbiotic algae.

7. Most flatworms are H______, meaning each individual containing both male and female sexual structures.

8. The most primitive bilaterally symmetrical and the simplest acoelomatic animals in which organs occur are the F______.

9. A protostome coelomate organism which increases in size by molting the external skeleton is placed in the Ecd______clade according to rRNA sequences.

10. The most prominent phylum of acoelomates, P______, includes the free-living flatworms and the parasitic flukes and tapeworms.

11. R______are small, free-living pseudocoelomates, often smaller than some ciliate protists.

12. ______Which of the following is not a characteristic of the Lophotrochozoans clade which is based on rRNA sequences? A. protostomes B. growth by adding mass to existing body C. appearance of free-living trocophore larvae in many of the organisms’ life cycles D. mainly aquatic E. pseudocoelomate 13. ______Two phyla which belong to the Ecdysozoan clade are A. Platyhelminthes and Nematoda B. Nematoda and Arthropoda C. Annelida and Mollusca D. Mollusca and Arthropoda E. Platyhelminthes and Arthropoda

14. ______Sponges are unique in possessing special flagellated cells whose beating drives water through the body cavity. These specialized cells are known as A. cnidocytes B. planulae C. nematocysts D. chaonocytes E. spicules

15. ______Radially symmetrical marine animals that propel themselves through the water by means of eight comb-like plates of fused cilia belong to the Phylum A. Cnidaria B. Ctenophora C. Platyhelminthes D. Eumetazoan E. Parazoa

16. ______Most species of tapeworms live in the A. stomachs of vertebrates B. lungs of vertebrates C. livers of vertebrates D. intestines of vertebrates E. hearts of vertebrates

17. ______Which of the following is not one of the key transitions in body design that are responsible for most of the differences among the major animal phyla? A. nonmoving to moving bodies B. radial to bilateral symmetry C. no body cavity to body cavity D. unsegmented to segmented bodies E. protostome to deuterostome development

18. ______Sponges exhibit all of the following general characteristics except A. eat by flow of water through canals and pores B. free-swimming larvae; sessile adults C. lack of specialized tissues and organs D. lack of symmetry (may be radial in small species) E. three cell layers—ectoderm, endoderm, and mesoderm 19. ______The vase-like body of a simple sponge is likely to contain all of the following materials or layers except A. a digestive cavity lined with enzyme-secreting cells B. mesophyl, a protein-rich matrix C. a somewhat contractile outer epithelium D. specialized collar cells or choanocytes E. spicules or a spongin skeleton, or both

20. ______All of the following are true about Cnidarians except A. they are widespread and abundant especially in shallow, warm-temperature or subtropical waters B. they are basically gelatinous in composition C. their bodies are made up of distinct organs D. they exist either as polyps or medusae E. they contain specialized cells called “cnidocytes” within which nematocysts are found

21. ______Which of the following belongs to the phylum Ctenophorans? A. hydra B. jellyfish C. anemones D. comb jellies E. corals

22. ______Anthozoan corals are characterized by all of the following except A. some may have hard calcium carbonate exoskeletons B. the coral animals are always found in nutrient-rich waters C. some participate in the formation of shallow-water limestone ridges D. many harbor symbiotic algae E. they are a class of Cnidarians

23. ______Phylum Platyhelminthes is characterized by all of the following except A. bilateral symmetry B. solid bodies with an inner digestive cavity C. flat ribbon-shaped bodies with dorso-ventral parts and anterior head D. all are free-living E. possess an excretory system

24. ______Flatworms are similar to sponges, Cnidarians, and Ctenophores in which of the following? A. contain an excretory system lined with a network of fine tubules running through the body B. contain an incomplete gut with only one opening C. cilia line the hollow centers of bulb-like flame cells D. lack circulatory systems for transport of oxygen and food E. most are hermaphroditic

25. ______Flukes are parasitic worms whose hosts during the larval stage are usually A. aquatic insects B. cyprinid fishes C. humans D. other free-living flatworms E. snails 26. ______The stage in the fluke's life history in which it escapes from the snail and is ready to enter the intermediate or final host is the A. cercariae B. fertilized eggs C. miracidia D. rediae E. sporocytes

27. ______Schistosomiasis is a serious disorder afflicting humans mainly in tropical regions; it is caused by a A. carp or goldfish B. fluke C. nematode D. snail E. tapeworm

28. ______The long, flat bodies of tapeworms are made up of repeating segments known as A. antheridia B. gut blocks C. proglottids D. scolex E. miracidia

29. ______Which of the following is not true about beef tapeworms? A. occur as a juvenile in the intermuscular tissue of cattle B. found as an adult in the intestines of human beings C. able to produce embryos, which may be viable for up to five months D. able to reach adult length of up to 10 meters E. more than 10% of the cattle are infected in the United States

30. ______Which of the following is not true about pseudocoelomates? A. they possess an internal body cavity called a pseudocoel B. they contain a bony skeleton C. they possess a complete, one-way digestive tract D. the pseudocoel permits resistance to muscle contraction E. they lack a defined circulatory system