Chapter 28: Invertebrate Evolution

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Student:_______________________________________________

Multiple Choice Questions 1. Animals are classified based on all of the following features EXCEPT

A) segmentation. B) mode of reproduction. C) body symmetry. D) germ layers. E) embryological development patterns.

2. Which of the following is NOT a characteristic of the porifera? A) spicules B) two tissue layers C) osculum D) amoeboid cells E) asexual reproduction

3. Obelia (a common hydroid cnidarian) has all of the following characteristics EXCEPT A) polyp stage is colonial B) nematocysts C) alternation of generations D) bilateral symmetry E) a medusa stage

4. Which of the following is NOT a characteristic of all animals? A) They ingest food. B) They produce gametes by meiosis. C) They reproduce asexually by mitosis. D) With the exception of sponges, food is digested in a central cavity. E) The adult form of most animals is diploid.

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5. Which statement is NOT true about invertebrate animals? A) The majority of animal species are invertebrates. B) Many invertebrate species live in a marine environment. C) Most animal phyla are invertebrate. D) Fossils of all major invertebrate species are known from the start of the

Cambrian period. E) Invertebrates lack a nervous system.

6. Animals that have three layers of embryonic tissue and have one solid mass of tissue rather than tissues and organs nestled inside a body cavity are A) acoelomate. B) eucoelomate. C) pseudocoelomate. D) quasicoelomate. E) coelomate.

7. Animals that have three layers of embryonic tissue but have organs in a cavity that is not completely lined with mesoderm are A) acoelomate. B) eucoelomate. C) pseudocoelomate. D) quasicoelomate. E) coelomate.

8. Animals that have three layers of embryonic tissue with organs in a cavity that is completely lined with mesoderm are A) acoelomate. B) eucoelomate. C) pseudocoelomate. D) quasicoelomate. E) coelomate.

9. Coelomates that develop with the blastopore becoming the mouth are A) gastrocoelomate. B) blastocoelomate. C) protostomes. D) deuterostomes. E) triploblastic.

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10. A recent study of the marine hawksbill turtles' stomach contents revealed that

sponges constitute a major portion of their diet. Sponge beds are generally protected from predators by their calcium and silica crystals, but these were found in the turtles' digestive systems. These protective sponge structures are A) amoebocytes. B) osculum. C) choanocytes. D) spicules. E) spongin.

11. Press a sponge through a coarse cloth bag and extrude the whole cells through the holes. The cells then A) reproduce sexually. B) die from being separated. C) form spicules in the pattern of the cloth. D) all go back to primitive cells and soon differentiate into another sponge. E) reassemble into a new organized sponge with each cell resuming its original

job.

12. Why are genuine bath sponges (rare) so soft?

A) The silica is washed away and the calcium carbonate remains. B) The spongin spicules are washed away and the silky silica remains. C) The choanocytes are softer and the amoebocytes are washed away. D) The harder silica or calcium spicules are broken and washed away and the

softer spongin remains. E) None of these is the reason for the softness of sponges.

13. Which of these is NOT a characteristic of sponges? A) sessile filter feeders B) body wall has two cell layers C) flagellated collar cells move water D) water enters through a single cavity, the osculum E) amoeboid cells digest food and make skeletal fibers and gametes

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14. Which statement about sponges is NOT correct?

A) The larval form is ciliated and able to swim to a suitable location. B) Sponges are classified on the basis of their type of skeletal material. C) Sponges resemble a colony of protozoan cells more than a multicellular

animal. D) Sponges are thought to be on the evolutionary pathway leading to more

complex animals such as corals and worms. E) Sponges do not have true tissues.

15. Of the following organisms, which is the most evolutionarily advanced, with more complex body structure? A) roundworms B) cnidaria C) sponges D) flatworms E) comb jellies

16. Which of the following statements about sponges is NOT correct? A) Sponges have no nerve fibers. B) Sponges have no fully developed muscle fibers. C) Amoeboid cells capture food particles from the water. D) Sponges may reproduce asexually by budding or by regeneration from a

small piece. E) Cells of a single sponge will recognize others of the same kind and re-

aggregate if the cells are separated and allowed to re-associate.

17. Which of the following are NOT cnidaria?

A) corals B) planaria C) sea anemones D) hydrozoa E) Portuguese man-of-war

18. Which of the following statements is NOT correct about cnidaria? A) The adult body is bilaterally symmetrical. B) Most are found in shallow coastal marine environments. C) There are two tissue layers, an outer epidermis and inner gastrodermis. D) Stinging cells contain a threadlike nematocyst released to capture prey. E) A jellylike mesoglea contains cells that form a nerve net throughout the

body.

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19. Which body structure describes the freshwater hydra? A) a swimming medusa with mouth pointing downward B) a swimming medusa with mouth pointing upward C) a sessile medusa with mouth pointing upward D) a sessile polyp form with mouth pointing downward E) a freely moving polyp with mouth pointing upward

20. A hydra moves by using A) nematocysts. B) alternation of generations. C) contraction of the nerve net. D) epitheliomuscular cells in the epidermis. E) epitheliomuscular fibers in the mesoglea.

21. How do Obelia reproduce sexually? A) Male polyps and female polyps produce sperm and eggs, respectively, that

fuse and grow into a medusa. B) The swimming medusae are male and female and the fertilized eggs develop

into planula larvae. C) They produce a polyp that makes sperm and eggs (like a hydra) and grows

into another polyp. D) The swimming medusae are male and female and the fertilized eggs develop

into more jellyfish medusae. E) All of the choices are correct.

22. What system do the cnidaria and comb jellies have that sponges lack? A) respiratory B) nervous C) circulatory D) excretory E) reproductive

23. A floating Portuguese man-of-war is A) an anthozoan. B) merely a non-circular jellyfish. C) a free-swimming single polyp in the hydra group. D) the first animal with complete organ systems. E) a colony composed of different types of individuals polyps.

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24. Which statement about cnidaria is NOT true?

A) Reproduction is both sexual and asexual. B) Some forms are sessile and others are motile. C) They live in either marine or freshwater environments. D) Tentacles are used to capture prey and put it into the mouth. E) The body plan is tube-within-a-tube, with both mouth and anus.

25. Which of the following is correct in matching the common name with a phylum name? A) planarian—Nematoda B) fluke—Platyhelminthes C) coral—Porifera D) roundworm—Cnidaria E) sponge—Anthozoa

26. In flame cells, A) light is detected. B) ciliated sperm are stored. C) undigested food is expelled. D) slow fires actually burn food for energy. E) cilia drive fluids through tubules for excretion.

27. Planaria move by A) flame cells. B) small pseudopodia. C) lateral undulation of muscles. D) expulsion of fluids as with squid. E) secreting a film of mucus and pushing against it with epidermal cilia.

28. Flukes are divided into Monogenea and Digenea. Monogenea have a posterior holdfast with hooks, clamps, and suckers; Digenea have suckers but never hooks and clamps. Monogenea have only one host in the life cycle, and usually live on gills or skin of fish and amphibians; Digenea have at least two hosts and often three or more, and are named because they have two reproductive states in their life cycle (an adult and intramolluscan phase). From what you now know, the blood fluke Schistosoma would therefore be A) an endoparasite and Monogenean. B) an endoparasite and Digenean. C) an ectoparasite and Digenean. D) an ectoparasite and Monogenean. E) None of the above. Blood flukes are in a group all their own.

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29. A person working in a rice paddy in Asia becomes infected with the liver fluke by A) eating infected snails. B) drinking water contaminated with eggs. C) eating infected undercooked or uncooked fish. D) swimming or wading in infected water, where the cercariae enter the skin. E) being bitten by a certain species of mosquito.

30. Which of the following statements is NOT correct about the flatworms? A) There are three complete tissue layers. B) Flatworms may be either free-living or parasitic. C) Flatworms have a sac body plan, with only a mouth and no anus. D) Parasitic flatworms have a well-developed head with eyespots and nerves

concentrated into a brain. E) Parasitic flatworms utilize secondary or intermediate hosts.

31. Which of the following statements is NOT true about the flatworms? A) Tapeworms have a well-developed nervous system. B) Planaria contain pigmented, photosensitive eyespots. C) Liver flukes and blood flukes are endoparasites in humans. D) Schistosomiasis is a common human blood disease caused by flukes in

tropical areas. E) Tapeworms are hermaphroditic, having both male and female reproductive

structures in each proglottid.

32. How might a human become infected with adult tapeworms?

A) eating insufficiently cooked pork B) being bitten by a mosquito C) ingesting eggs in contaminated water D) eating freshly peeled fruit E) All of the choices are correct.

33. The head region of a tapeworm is called the A) proglottid. B) cercaria. C) sporocyst. D) scolex. E) glycocalyx.

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34. The segments of a tapeworm consisting primarily of eggs, which hang in bags as

a long chain behind the head, are called A) proglottids. B) cercariae. C) sporocysts. D) scolexes. E) glycocalyxes.

35. Which of the following statements about planaria is NOT true? A) There is a rudimentary circulatory system with a small central heart. B) Planaria cut in half can regenerate to form two complete worms. C) Active movement occurs through ciliary cells and muscle movement. D) Tissue levels include endoderm (inner), mesoderm (middle), and ectoderm

(outer). E) Cephalization is shown by the formation of a brain and sense organs in a

head region.

36. Which of these statements is NOT correct about the flatworms?

A) Planaria have an excretory system. B) Planaria ingest food through a mouth located in the head region. C) Flukes have two suckers by which they attach to and feed from host tissues. D) Tapeworms have a scolex with hooks and suckers, by which they attach to

the host's intestinal tissues. E) Tapeworms enter the human body through undercooked meat, especially

pork, which contains encysted larval forms.

37. The term "pseudocoelom" is based on the Greek words for

A) a mythological many-headed serpent. B) false backbone. C) false cavity. D) head development. E) lack of a cavity.

38. Which statement is NOT correct about the roundworms? A) There are three layers of tissues in the body. B) Roundworms have a tube-within-a-tube body plan. C) There is an internal body cavity called a pseudocoelom. D) Roundworms have a smooth unsegmented outside body wall. E) Roundworms are all carnivores and may be free-living or parasitic.

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39. Which of these parasitic worms is NOT a nematode? A) Ascaris B) Trichinella C) Wuchereria D) pinworms E) Schistosoma

40. Larval Trichinella worms live in the A) liver. B) lungs. C) intestines. D) lymph glands. E) skeletal muscle.

41. Elephantiasis is an enlargement of legs, arms, scrotum, and other tissues caused

by A) an infection of the human coelom by Ascaris. B) a large number of Trichinella worms encysting in our muscles. C) contracting a disease that usually occurs in elephants. D) microscopic roundworms that reproduce and clog lymph glands, causing

limbs to swell. E) a protozoan that lives in tropical roundworms and, when ingested by

humans, causes muscles to bloat.

42. Classification of animals is based upon all of the following EXCEPT

A) level of organization. B) type of body plan. C) type of symmetry. D) type of coelom. E) presence or absence of a nervous system.

43. Bilaterally symmetrical animals A) tend to be active and move forward. B) are accompanied by cephalization. C) have right and left sides when cut longitudinally. D) have an anterior and posterior end. E) All of the choices are correct.

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44. Radially symmetrical organisms

A) are organized circularly—all longitudinal cuts result in identical halves. B) are sometimes sessile. C) can reach in all directions. D) lack cephalization. E) All of the choices are true.

Matching Questions Use the following diagrams that represent three body plans found in the animal kingdom to answer questions 45-50:

45. Which diagram above (A, B, or C) represents a coelomate?

46. Which diagram represents a pseudocoelomate? 47. Which of the following animals would have a body plan like the one labeled “C”?

A) cnidarian B) flatworm C) roundworm D) earthworm E) sponge

48. Which of the following animals would have a body plan like the one labeled “A”? A) flatworm B) roundworm C) rotifer D) earthworm E) sponge

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49. The innermost cavity that is common to each of the three body plans is the

A) coelom. B) pseudocoelom. C) digestive cavity. D) gastrovascular cavity. E) spongocoele.

50. The outermost layer of tissue of each of the diagrams on the previous page is the A) mesoderm. B) ectoderm. C) endoderm. D) gastroderm. E) periderm.

51. Which organism does not use gills for respiration?

A) clam B) lobster C) squid D) crab E) earthworm

52. The first phylum to have a true coelom is A) arthropods. B) molluscs. C) echinoderms. D) roundworms. E) chordates.

53. Similarities between polychaetes and oligochaetes include all of the following EXCEPT A) segmentation. B) closed circulatory system. C) both are predators. D) nephridia. E) ventral solid nerve cord.

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54. Which of the following is NOT an advantage of having a true coelom?

A) Sperm and eggs can be stored before they are released. B) The digestive system can coil and provide greater surface area. C) Muscle contractions against the fluid chambers are absorbed and have no

effect. D) Fluids here can assist respiration and circulation, and accumulate metabolic

wastes. E) Complex organ systems can develop protected from damage and

temperature changes.

55. In which way are protostomes and deuterostomes the same?

A) They both have spiral cleavage of the embryo. B) The coelom develops in the same way in both. C) The mouth forms first in both, before the anus. D) They both form a hollow sphere in the embryo that has an indentation called

a blastopore. E) They both have indeterminate fate of the embryonic cells, so that separated

cells all have the capacity to become a complete embryo.

56. Which of the following is a deuterostome?

A) snail B) octopus C) sea star D) earthworm E) insect

57. Which of the following show embryonic development by the deuterostome pathway? A) annelids B) chordates C) mollusks D) arthropods E) All of the choices are correct.

58. Which are NOT among the phylum Mollusca? A) clams B) squids C) lobsters D) nautiluses E) snails

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59. Which characteristic is NOT found in the class Gastropoda?

A) anus directly over the head B) torsion of the body so that the visceral mass is over the foot C) mantle may form gills or functional lungs D) carnivores use the radula to drill holes in shells of bivalves E) swimming larvae are found in all forms

60. A unique species of snail has been discovered in the Negev Desert. At night, these snails use a tooth like rasping organ in their head to scrape up porous limestone; they then digest the algae that lived in the rock pores. This scraping organ is the A) labial palp. B) radula. C) mantle. D) tentacle. E) crop.

61. Which of these is a bivalve? A) slug B) octopus C) earthworm D) snail E) oyster

62. The most intelligent of the invertebrates is thought to be the A) earthworm. B) insect. C) nudibranch. D) octopus. E) spider.

63. The term "cephalopoda" is based on the Greek words for A) soft-headed. B) no-backbone. C) head-footed. D) stomach-footed. E) many-bristles.

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64. The cephalopods resemble other mollusks because they have

A) focusing camera-type eyes. B) a siphon for jet-propulsion. C) a parrotlike beak for tearing prey. D) well-developed brains with high learning capacity. E) most of the internal organs located in a visceral mass.

65. The term "gastropoda" is based on the Greek words for A) soft-headed. B) no-backbone. C) head-footed. D) stomach-footed. E) many-bristles.

66. The larval stage of most marine worms–which is nearly identical to the larvae of mollusks and which shows their evolutionary relationship–is the A) bipinnaria larvae. B) miracidium. C) cercariae. D) trochophore larvae. E) glochidia.

67. In animals, the prefix “nephro-“ refers to what organ? A) liver B) kidney C) heart D) stomach E) lungs

68. The term "Oligochaeta" is based on the Greek root word for A) earth-worm. B) large-bristles. C) head-footed. D) few-long hair. E) many-long hair.

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69. A closed circulatory system is found in

A) insects. B) snails. C) clams. D) earthworms. E) scorpions.

70. The structures that earthworms use to anchor themselves in the earth and pull themselves along are A) aortic arches. B) lateral ventricles. C) setae. D) parapodia. E) nephridia.

71. Nematodes were roundworms that could ''wiggle'' back and forth because an inelastic cuticle restored the shape when longitudinal muscles relaxed. A segmented worm A) works the exact same way. B) forcibly extends its body by using longitudinal muscles in reverse. C) contracts circular muscles and forcibly elongates using this hydrostatic

skeleton. D) has many more longitudinal muscles, giving it more movement ability than

roundworms. E) contracts circular muscle in order to shorten up.

72. Earthworms secrete the enzyme cellulase to digest the cell walls of plant root fibers consumed with soil. This enzyme would most likely be found in the ___________ which is responsible for digestion and absorption. A) nephridia B) buccal cavity C) crop D) intestine E) esophagus

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73. When an earthworm secretes a slime layer to receive eggs and sperm and form a

''cocoon,'' this secretion is produced by the A) annulations. B) peritoneum. C) clitellum. D) nephridium. E) prostomium.

74. Earthworms differ from most of the marine annelids in that earthworms A) lack setae that marine annelids have. B) lack paddle-like parapodia that marine annelids have. C) have segments, whereas marine annelids do not. D) develop from a larval form, whereas marine annelids do not. E) have well-developed brains and sensory organs in the head region, whereas

marine annelids do not.

75. To which phylum do leeches belong?

A) Mollusca B) Arthropoda C) Chordata D) Echinodermata E) Annelida

76. Why does the wound from the bite of a leech bleed profusely? A) The bacteria in leeches prevents clotting. B) Leech saliva contains a strong anticoagulant. C) The bite is made underwater, and blood doesn't clot in water. D) The leech is really feeding on tissue proteins, and the constant cutting at

tissues causes continuous hemorrhaging in water. E) The leech typically bites into a major artery.

77. With regard to number of species, which of the following is the largest animal phylum? A) Mollusca B) Arthropoda C) Chordata D) Echinodermata E) Annelida

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78. The term "arthropoda" is based on the Greek words for A) few-bristles. B) stomach-footed. C) joint-footed. D) head-footed. E) many-bristles.

79. Which combination of taxon and organism is NOT correct? A) Insecta—beetle B) Gastropoda—conch C) Annelida—lobster D) Oligochaeta—earthworm E) Crustacea—barnacle

80. It is NOT correct to say that arthropods have A) a solid ventral nerve cord. B) an open circulatory system. C) a well-developed nervous system. D) jointed appendages and a segmented body. E) a tough exoskeleton that grows by expansion.

81. An insect circulatory system is best described as A) totally closed like ours, with arteries and veins. B) similar to ours with general closed vessels but no distinct arteries and veins. C) an open system that mostly washes "blood'' through the body cavities. D) totally absent; each body cell manages on its own to gain food and get rid of

wastes. E) relying on coelomic fluid to distribute materials.

82. The insect organ most equivalent to the human lung in function is the A) tracheae. B) midgut. C) crop. D) gizzard. E) Malpighian tubule.

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83. The major insect body parts are

A) head, cephalothorax, and abdomen. B) cephalothorax, midsection, and abdomen. C) head, thorax, and abdomen. D) head, prothorax, and metathorax. E) head, cephalothorax, and genitalia.

84. The term "hemocoel" is based on the Greek words for A) no cavity. B) digestive cavity. C) blood cavity. D) red cavity. E) false cavity.

85. Millipedes differ from centipedes because A) centipedes generally have fewer legs per segment. B) the millipede is herbivorous, the centipede is carnivorous. C) large centipedes are dangerous to handle but millipedes are safe. D) millipedes have cylindrical bodies and centipedes are more flattened. E) All of the choices are correct.

86. The horseshoe crab Limulus is a/an A) insect. B) chelicerate. C) crustacean. D) ancient spider. E) mollusk.

87. Spiders have A) antennae. B) chelicera modified as fangs. C) compound eyes. D) an abdominal stinger with venom. E) All of the choices are spider characteristics.

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88. Which statement about arachnids is NOT true?

A) Ticks and mites are often parasitic. B) Spiders and scorpions are predators. C) Spiders have both simple and compound eyes. D) Spiders have a pair of fangs which release poison. E) The body parts include a cephalothorax and an abdomen.

89. An arachnid differs from a crustacean because A) arachnids lack antennae. B) arachnids are mostly aquatic and crustaceans are mostly terrestrial. C) only arachnids shed their exoskeletons. D) only arachnids have two major body segments of cephalothorax and

abdomen. E) All of the choices are correct.

90. Protostomes development includes all of the following EXCEPT A) spiral cleavage. B) daughter cells sit in grooves formed by prior cleavage. C) cell fate is fixed and can develop in only one way. D) blastopore becomes the anus. E) All of these are protostome characteristics.

91. All of the following are protostomes EXCEPT A) Crustaceans. B) Annelids. C) Echinoderms. D) Mollusks. E) Insects

92. Mollusks are characterized by A) a visceral mass and mantle. B) a foot. C) a nervous system consisting of several ganglia connected by nerve cords. D) hemolymph with hemocyanin is the respiratory pigment. E) All of these choices characterize mollusks.

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93. Which of the following is NOT a Mollusk?

A) Bivalvia B) Cephalopoda C) Echinodermata D) Gastropoda E) Polyplacophora (chitons)

94. Earthworms possess all of the fundamental organ systems that reach their full development in humans. One major difference is A) an excretory system. B) a reproductive system. C) a closed circulatory system. D) a hydrostatic skeleton. E) a digestive system with specialized organs.

95. Which of the following is a marine arthropod? A) barnacle B) clam worms C) Grasshoppers D) millipedes E) nautilis

96. The term based on the Greek words for "spiny skinned" is A) echinoderm. B) protostome. C) cephalochordata. D) deuterostome. E) chondrichthyes.

97. Sea stars and sea urchins operate their tube feet by A) a hydraulic system that regulates water pressure. B) cilia transporting hemolymph from chamber to chamber. C) sticky threads leading from the mouth. D) actin and myosin fibers that slide and give muscle actions to the five arms or

''rays.'' E) forcing seawater through their siphons.

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98. The only one of these phyla with NO terrestrial forms is

A) Echinodermata. B) Arthropoda. C) Chordata. D) Mollusca. E) Annelida.

99. The madreporite helps the sea star A) reproduce. B) locate food. C) digest food and distribute it to the arms. D) take in water to operate its water-vascular system. E) keep its surface clean of algae and barnacles and debris.

100. Sea stars reproduce A) by budding. B) by asexual processes alone. C) sexually, with separate sexes. D) sexually, with both sex organs on the same organism similar to earthworms. E) All of these are part of diverse reproductive strategies of sea stars.

101. A sea star's nervous system includes A) no actual nerve cells. B) a complex of nerve ganglia in each ray. C) a central nervous system, including a brain. D) a central nerve ring that gives off radial nerves in each arm. E) a ventral nerve cord running down one ray.

102. Which statement is NOT true about echinoderms? A) They have an exoskeleton made up of spiny plates. B) Gas exchange occurs through structures called skin gills. C) Larvae are free-swimming and bilaterally symmetrical. D) A water vascular system allows the tube feet to produce suction. E) Symmetry is radial in the adult, usually with parts in fives or multiples of

five.

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103. Sea Stars are Echinoderms that

A) use a water vascular system for locomotion. B) have a well developed coelom containing digestive glands and gonads in

each arm. C) lack a complex respiratory, excretory, or circulatory system. D) have a one-way digestive tract with a mouth and anus. E) All of these choices characterize sea stars.

Matching Questions Use the following diagram to answer questions 104-113:

104. carry out excretion using paired nephridia

105. body composed of cephalothorax and abdomen

106. carry out excretion using green glands

107. feed using a radula

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108. possess a water-vascular system

109. carry out excretion using Malpighian tubules

110. skin serves as the organ of respiration

111. respire with the aid of spiracles and tracheae

112. member of the deuterostomes

113. terrestrial forms of this animal breathe through a primitive lung

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Essay Questions

114. Although the majority of mollusks and annelids are marine or aquatic, both

phyla possess members that made the transition to land, though they remain somewhat limited in their distribution. A) Describe the terrestrial members of each phylum, discuss the necessary

adaptations they had to make that allowed them to survive on land and describe what limitations they face as land animals.

B) Discuss why insects (as members of Arthropoda) were so much more successful as land animals.

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115. Embryological development patterns are used as a valuable tool for determining

evolutionary relationships. Discuss how body features such as symmetry, germ layers (endoderm, ectoderm, mesoderm) and body cavities give us an idea of the pattern of evolution from cnidarians to flatworms to roundworms to segmented worms.

116. All animals no matter how simple must still carry out the basic functions of

respiration, excretion of metabolic wastes, circulation, and digestion (among others). Choose two of the simple animals below and describe the structures and processes used by these animals to carry out the four functions mentioned above. A) sponge B) hydra C) planarian D) roundworm