Ch 33.docx

Ch 33 Almost all bilaterian animals belong to either of clade Protostomia and clade Deuterostomia. - Answer: Protostomia and Deuterostomia The two major groups of protostome are Lophotrochozoa and Ecdysozoa. - Answer: Lophotrochozoa and Ecdysozoa Flatworms are found in aquatic and in moist terrestri...

Ch 33 Almost all bilaterian animals belong to either of clade Protostomia and clade Deuterostomia. - Answer: Protostomia and Deuterostomia The two major groups of protostome are Lophotrochozoa and Ecdysozoa. - Answer: Lophotrochozoa and Ecdysozoa Flatworms are found in aquatic and in moist terrestrial environments. - Answer: Aquatic and moist terrestrial Immediately once they are released from the proglottid, tapeworm embryos are scattered in the environment. - Answer: are scattered in the environment. Members of the phylum Rotifera are tiny (50 to 500 μm), bilaterally symmetrical pseudocoelomates that often live in freshwater environments and use adhesive toes for clinging on vegetation and other solid objects. - Answer: Rotifera In deuterostomes, the blastopore gives rise to the anus. - Answer: anus Squid, octopuses, chitons, snails, clams, and oysters are all members of the phylum Mollusca. - Answer: Mollusca The protostomes are divided into the Lophotrochozoa and Ecdysozoa. - Answer: Lophotrochozoa and Ecdysozoa Terrestrial habitats of mollusks must have at least a temporary supply of moisture. - Answer: moisture In which habitats are flatworms found? - Answer: Freshwater, marine, and moist terrestrial habitats. The basic body plan of a mollusk consists of three parts: a muscular foot, a visceral mass, and a mantle. - Answer: muscular foot, visceral mass, and mantle Embryos are released from a proglottid by rupture of the proglottid and emergence from a pore on the proglottid. - Answer: rupture of the proglottid and emergence from a pore on the proglottid What is the mantle of a mollusk? - Answer: An epidermal sheet covering the dorsal side of the body. What are distinguishing characteristics of members of phylum Rotifera? - Answer: They are very small in size, have a complete gut, and are pseudocoelomate. What secretes the calcium carbonate of the shell in a mollusk? - Answer: The mantle. Each segment of an annelid contains which of the following? - Answer: A ganglion, excretory organs, and locomotory structures. In mollusks, what is the unique, protrusible, tongue-like organ used for feeding called? - Answer: Radula. The muscular foot of a mollusk may be adapted for what? - Answer: Locomotion, attachment, food capture, or digging. Polyplacophorans are commonly known as what? - Answer: Chitons. Gastropods are unique among animals in that they undergo what during larval life? - Answer: Torsion. Which of the following is a major advantage of segmentation? - Answer: Individual segments can become specialized for different functions. The shell of a mollusk is secreted by the outer surface of its what? - Answer: Mantle. What part of a mollusk secretes its shell? - Answer: The mantle. What type of circulatory system do annelids have? - Answer: Closed circulatory system. Which of the following accurately describes the function of the radula in mollusks? - Answer: It is used in feeding. What are characteristics of the class Chelicerata? - Answer: Bodies consist of two tagmata, and mouthparts can be modified as pincers or fangs. Which organisms are included in the class Myriapoda? - Answer: Centipedes and millipedes. What are characteristics of the class Chelicerata? - Answer: Mouthparts can be modified as pincers or fangs, and bodies consist of two tagmata. What organisms are included in the class Myriapoda? - Answer: Centipedes and millipedes. Arthropods play a role in what? - Answer: The pollination of crops, the destruction of crops, and the spreading of serious diseases. What characteristics are typical of the class Chelicerata? - Answer: Mouthparts can be modified as pincers or fangs, and bodies consist of two tagmata. The class Hexapoda includes what? - Answer: Insects. What organisms are included in the class Myriapoda? - Answer: Centipedes and millipedes. Arthropods play a role in what? - Answer: The pollination of crops, the destruction of crops, and the spreading of serious diseases. Which of the following accurately describes chelicerates? - Answer: Most are carnivorous and have four pairs of walking legs. The class Hexapoda includes what? - Answer: Insects.