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Chapter 14 1. Specialization of Regions of the Body for Specific Chapter 14 1. Specialization of regions of the body for specific functions, as seen in arthropods, is called A) tagmatization. B) metamerism. C) truncation. D) differentiation. E) cephalization. 2. Members of class __________ are among the most numerous crustaceans, and are both marine and freshwater in distribution. A) Cirripedia B) Copepoda C) Branchiopoda D) Malacostraca E) Isopoda 3. Which type of crustacean do many zoologists believe to have the greatest number of individuals of any type of animal on the planet? A) isopods B) fairy shrimp C) brine shrimp D) copepods E) barnacles 4. Which of the following phyla of animals are not ecdysozoan? A) Arthropoda B) Nematoda C) Gastrotricha D) Nematomorpha E) Kinorhyncha 5. Which of the following is not a synapomorphy that unites the members of the ecdysozoan clade? A) the blastopore develops into the anus B) loss of epidermal cilia C) possession of a cuticle D) shedding of cuticle through ecdysis E) all of the above are synapomorphies shared by ecdysozoans Page 1 6. The __________ is the outer layer of the arthropod exoskeleton, and it is composed of a waterproofing waxy lipoprotein. A) lipocuticle B) mesocuticle C) epicuticle D) endocuticle E) sclerocuticle 7. The tough, leathery polysaccharide in the arthropod procuticle is A) lipoprotein. B) calcium carbonate. C) scleroprotein. D) chitin. E) glycogen. 8. The arthropod skeleton hardens by __________, which is a formation of chemical bonds between protein chains. A) carbonization B) tagmatization C) calcification D) chitinization E) sclerotization 9. Sensory receptors called __________ occur in the arthropod exoskeleton in the form of pegs, bristles, and lenses. A) sensilla B) tactiles C) olfactors D) cirri E) palps 10. The arthropod exoskeleton must be shed to allow growth. The shedding process is called A) sclerotization. B) ecdysis. C) calcification. D) articulation. E) metamorphosis. Page 2 11. __________ between larval and adult stages of arthropods reduces competition for resources. A) Asexual reproduction B) Regeneration C) Metamorphosis D) Ecdysis E) Parthenogenesis 12. The extinct arthropod subphylum Trilobitomorpha was named for A) the three known stages of the life cycle. B) the three known larval forms. C) the three geologic ages which were dominated by trilobites. D) the three longitudinal body divisions. E) the three species which have been identified. 13. Appendages of trilobites were divided into two lobes, hence they are called A) biped. B) uniramous. C) quadruped. D) aramous. E) biramous. 14. Horseshoe crabs belong to the arthropod subphylum A) Chelicerata. B) Arachnida. C) Uniramia. D) Crustacea. E) Mandibulata. 15. Chelicerates have a cephalothorax, also known as the __________, which functions in sensation, feeding, and locomotion. A) chelicera B) prosoma C) abdomen D) opisthosoma E) carapace 16. The chelicerate opisthosoma A) bears the pedipalps. B) is the sensory tagma. C) contains digestive organs. D) bears chelicerae. E) bears walking legs. Page 3 17. Gas exchange between the blood of horseshoe crabs and seawater occurs through A) filamentous gills. B) book lungs. C) alveolar lungs. D) book gills. E) dermal branchiae. 18. How many tagmata do animals in the order Araneae have? A) 1 B) 2 C) 3 D) 4 E) 5 19. Spiders, ticks, and scorpions belong to the arthropod class A) Chilopoda. B) Pycnogonida. C) Insecta. D) Merostomata. E) Arachnida. 20. Most zoologists believe that the __________ were the first arthropods to invade land. A) arachnids B) insects C) millipedes D) crustaceans E) centipedes 21. While aquatic arachnids utilize coxal glands for excretion, most terrestrial forms use __________ which conserve water. A) nephridia B) malpighian tubules C) diffusion glands D) green glands E) antennal glands 22. Many arachnids utilize __________ for respiration, which are believed to be modifications of book gills. A) lamellae B) alveolar lungs C) book lungs D) trachea E) malpighian tubules Page 4 23. A genus of scorpions known to have caused human deaths is A) Xiphosura. B) Opiliones. C) Loxosceles. D) Centuroides. E) Limulus. 24. Many spiders produce __________, that are used to trap small arthropods on which they feed. A) sticky oral secretions B) sandy pitfall traps C) oral venoms D) leaf traps E) webs 25. “Daddy longlegs” belong to the arachnid order A) Opiliones. B) Acarina. C) Pseudoscorpionida. D) Scorpionida. E) Aranaea. 26. The chigger or “red bug” is a member of the arachnid order A) Scorpionida. B) Acarina. C) Opiliones. D) Araneae. E) Pseudoscorpionida. 27. The bacteria that cause Lyme Disease are carried and transmitted by A) black widow spiders. B) tsetse flies. C) ticks. D) mosquitoes. E) mange mites. 28. Sea spiders belong to the class A) Merostomata. B) Chelicerata. C) Arachnida. D) Pycnogonida. E) Trilobita. Page 5 29. Crustaceans are unique among living arthropods as they possess A) chitin in their exoskeleton. B) one pair of antennae. C) only two pairs of walking legs. D) a carapace. E) two pairs of antennae. 30. The majority of crustaceans are A) aquatic. B) terrestrial. C) very large. D) burrowing animals. E) monoecious. 31. The portion of the crustacean exoskeleton that covers the cephalothorax is the A) locomotor tagma. B) carapace. C) telson. D) opisthosoma. E) uropod. 32. The crustacean abdominal appendages that are used for swimming are called A) scaphopods. B) pereiopods. C) pleopods. D) maxillipeds. E) chilipeds. 33. The biramous appendages of the crayfish are based on a similar ancestral pattern. This, and the sequential development of the segments makes them A) repetitively analogous. B) heteronomous. C) metachronous. D) serially homologous. E) homonomous. 34. Crustaceans have __________, which are sensory structures to provide information regarding gravitational orientation, movement and vibrations. A) papillae B) ommatidia C) antennules D) antennae E) statocysts Page 6 35. The crustacean compound eye is composed of individual units called A) ommatidia. B) ocelli. C) eyespots. D) statocysts. E) photophores. 36. The antennal or green glands of crayfish function in A) producing digestive enzymes. B) excretion. C) producing molting enzymes. D) sensing water quality. E) sensing gravity. 37. The primary excretory product of a crayfish is A) urine. B) ammonia. C) uric acid. D) sodium chloride. E) urea. 38. Brine shrimp and fairy shrimp are classified in the crustacean class A) Decapoda. B) Amphipoda. C) Branchiopoda. D) Anostraca. E) Isopoda. 39. The class of crustaceans with the largest number of species is A) Maxillopoda. B) Branchiopoda. C) Cladocera. D) Malacostraca. E) Decapoda. 40. Terrestrial crustaceans are quite rare, but terrestrial pill bugs belong to the order A) Amphipoda. B) Maxillopoda. C) Cladocera. D) Anostraca. E) Isopoda. Page 7 41. Barnacles belong to the A) Cirripedia. B) Hexapoda. C) Amphipoda. D) Malacostraca. E) Branchiopoda. 42. Krill belong to the order A) Amphipoda. B) Euphausiacea. C) Cladocera. D) Anostraca. E) Isopoda. 43. Adult barnacles are unusual in lifestyle because they are A) motile. B) sessile. C) predatory. D) free-swimming. E) dioecious. 44. Crayfish, lobsters, and shrimps belong to the order A) Maxillopoda. B) Hexapoda. C) Decapoda. D) Amphipoda. E) Branchiopoda. 45. Many female crustaceans carry developing eggs protected by their A) pauropods. B) ogiverous legs. C) pereiopods. D) pleopods. E) uropods. 46. Some ________ demonstrate a primitive form of vivipary. A) crabs B) crayfish C) shrimp D) scorpions E) barnacles Page 8 .
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