32 and 33 test 3
12. The sharp, inch-long thorns of the crown-of-thorns sea star are its spines. These spines, unlike those of most other sea stars, contain a potent toxin. If it were discovered that crown-of- thorns sea stars do not make this toxin themselves, then the most likely alternative would be that this toxin is _____. A) derived from the nematocysts of its prey B) absorbed from the surrounding seawater C) an endotoxin of cellulose-digesting bacteria that inhabit the sea star's digestive glands D) injected into individual thorns by mutualistic corals which live on the aboral surfaces of these sea stars
A
17. Which tissue type, or organ, is NOT correctly matched with its germ layer tissue? A) nervous — mesoderm B) muscular — mesoderm C) stomach — endoderm D) skin — ectoderm
A
20. The nematocysts most likely reach the skin of sea slugs through branches of the _____. A) intestine B) excurrent siphon C) nephridium D) pseudocoelom
A
21. If you think of the earthworm body plan as a drinking straw within a pipe, where would you expect to find most of the tissues that developed from endoderm? A) lining the straw B) lining the space between the pipe and the straw C) forming the outside of the pipe D) forming the outside of the straw
A
21. The nematocysts of sea slugs should be most effective at protecting individual sea slugs from predation if the predators _____. A) remove small bites of flesh from sea slugs and have long-term memory B) remove small bites of flesh from sea slugs and have no long-term memory C) consume entire sea slugs in one gulp and have no long-term memory D) consume entire sea slugs in one gulp and have long-term memory
A
24. Nudibranchs usually have two rhinophores. However, if they had a single rhinophore, it could still carry out the function of two rhinophores, and with similar effectiveness, if this single rhinophore _____. A) had two branches, one directed to the left, the other to the right B) was located within the mantle cavity C) was as long as two rhinophores placed end to end D) had cilia whose power strokes directed water away from the surface of the slug
A
29. According to the graph, during which season(s) of the year is the relationship between the sea slug and its dinoflagellates closest to being commensal? A) winter B) spring C) summer D) spring and summer
A
3. Comb jellies may not be the most familiar animal to you, but they are critical in the food chain because they make up a significant portion of the planktonic biomass. Their feeding strategy is predatory and involves adhesives or mucus on their tentacles or other body parts. What feeding tactic do these animals use? A) suspension feeder B) fluid feeder C) deposit feeder D) food-mass feeder
A
30. Planarians lack dedicated respiratory and circulatory systems because _____. A) none of their cells are far removed from the gastrovascular cavity or from the external environment B) they lack mesoderm as embryos and, therefore, lack the adult tissues derived from mesoderm C) their flame bulbs can carry out respiratory and circulatory functions D) their body cavity, a pseudocoelom,
A
31. What was an early selective advantage of a coelom in animals? A coelom _____. A) contributed to a hydrostatic skeleton, allowing greater range of motion B) was a more efficient digestive system C) allowed cephalization and the formation of a cerebral ganglion D) allowed asexual and sexual reproduction
A
31. Which one of these mollusk groups can be classified as suspension feeders? A) bivalves B) gastropods C) chitons D) cephalopods
A
33. Which of these, if true, would support the claim that the ancestral cnidarians had bilateral symmetry? 1. Cnidarian larvae possess anterior-posterior, left-right, and dorsal-ventral aspects. 2. Cnidarians have fewer Hox genes than bilaterians. 3. All extant cnidarians, including Nematostella, are diploblastic. 4. β-catenin turns out to be essential for gastrulation in all animals in which it occurs. 5. All cnidarians are acoelomate. A) 1 and 4 B) 2 and 3 C) 2 and 4 D) 4 and 5
A
34. An organism that exhibits cephalization probably also _____. A) is bilaterally symmetrical B) has a coelom C) is segmented D) is diploblastic
A
40. What is the probable sequence in which the following clades of animals originated, from earliest to most recent? 1. tetrapods 2. vertebrates 3. deuterostomes 4. amniotes 5. bilaterians A) 5 → 3 → 2 → 1 → 4 B) 5 → 3 → 4 → 2 → 1 C) 3 → 5 → 4 → 2 → 1 D) 3 → 5 → 2 → 1 → 4
A
41. Look at the graph for Scutigerina weberi (note the scale of the y-axis) in the figure above. What is the best interpretation of these results? A) The centipede had its spiracles open the entire time. B) The centipede had its spiracles closed the entire time. C) The centipede had its spiracles open when carbon dioxide (CO2) emission peaked and closed when CO2 emission was low. D) The centipede had its spiracles closed when carbon dioxide (CO2) emission peaked and open when CO2 emission was low.
A
45. The heartworms that can accumulate within the hearts of dogs and other mammals have a pseudocoelom, an alimentary canal, and an outer covering that is occasionally shed. To which phylum does the heartworm belong? A) Platyhelminthes B) Arthropoda C) Nematoda D) Annelida
A
47. In a tide pool, a student encounters an organism with a hard outer covering that contains much calcium carbonate, an open circulatory system, and gills. The organism could potentially be a crab, a shrimp, a barnacle, or a bivalve. The presence of which of the following structures would allow for the most certain identification of the organism? A) a mantle B) a heart C) a body cavity D) a filter-feeding apparatus
A
51. The antennae of insects have a function most similar to that of _____. A) rhinophores B) dorsal plummules C) cerata D) chemoreceptors
A
53. Sarah observed that the mystery pond organisms never come up to the pond's surface. If she catches one of these organisms and observes closely, perhaps dissecting the organism, she should find _____. A) gills B) spiracles C) tracheae D) book lungs
A
56. Which of the following combinations correctly matches a phylum to its description? A) Echinodermata — bilateral symmetry as a larva, water vascular system B) Nematoda — segmented worms, closed circulatory system C) Cnidaria — flatworms, gastrovascular cavity, acoelomate D) Platyhelminthes — radial symmetry, polyp and medusa body forms
A
8. In individual insects of some species, whole chromosomes that carry larval genes are eliminated from the genomes of somatic cells at the time of metamorphosis. A consequence of this occurrence is that _____. A) we could not clone a larva from the somatic cells of such an adult insect B) such species must reproduce only asexually C) the descendants of these adults do not include a larval stage D) metamorphosis can no longer occur among the descendents of such adults
A
If a lung were to be found in a mollusc, where would it be located? A) mantle cavity B) incurrent siphon C) visceral mass D) excurrent siphon
A
Sponges _____. A) have larvae which are motile and move via the motion of cilia B) are the simplest diploblastic animals C) have a nerve net but not a central nervous system D) have feeding cells called dinoflagellates
A
The most recently discovered phylum in the animal kingdom (1995) is the phylum Cycliophora. It includes three species of tiny organisms that live in large numbers on the outsides of the mouthparts and appendages of lobsters. The feeding stage permanently attaches to the lobster via an adhesive disk and collects scraps of food from its host's feeding by capturing the scraps in a current created by a ring of cilia. The body is sac-like and has a U-shaped intestine that brings the anus close to the mouth. Cycliophorans are coelomates, do not molt (though their host does), and their embryos undergo spiral cleavage. 29. Which of these features is LEAST useful in assigning the phylum Cycliophora to a clade of animals? A) having a true coelom as a body cavity B) having a body symmetry that permits a U-shaped intestine C) having embryos with spiral cleavage D) lacking ecdysis (molting)
A
Trichoplax adhaerens (Tp) is the only living species in the phylum Placozoa. Individuals are about 1 mm wide and only 27 μm high, are irregularly shaped, and consist of a total of about 2000 cells, which are diploid (2n = 12). There are four types of cells, none of which are nerve or muscle cells, and none of which have cell walls. They move using cilia, and any "edge" can lead. Tp feeds on marine microbes, mostly unicellular green algae, by crawling atop the algae and trapping it between its ventral surface and the substrate. Enzymes are then secreted onto the algae, and the resulting nutrients are absorbed. Tp sperm cells have never been observed, nor have embryos past the 64-cell (blastula) stage. 36. Tp's body symmetry seems to be most like that of _____. A) most sponges B) cnidarians C) worms D) tetrapods
A
Which of the following is most likely to be aquatic? A) suspension feeder B) mass feeder C) deposit feeder D) fluid feeder
A
. The bivalves started to die one by one; only the undamaged shells remained. To keep the remaining bivalves alive, the teacher would most likely need to remove the _____. A) sea anemones B) sea star C) gastropods D) ectoprocts
B
1. A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom. Assuming that none of the following genes is absolutely conserved, which of the following would be the best choice on which to base the phylogeny? A) genes involved in chitin synthesis B) collagen genes C) β-catenin genes D) genes involved in eye-lens synthesis
B
12. Evidence of which structure or characteristic would be most surprising to find among fossils of the Ediacaran fauna? A) true tissues B) hard parts C) bilateral symmetry D) embryos
B
14. You find what you believe is a new species of animal. Which of the following characteristics would enable you to argue that it is more closely related to a flatworm than it is to a roundworm? A) It is a suspension feeder. B) It has no coelom. C) It is shaped like a worm. D) It has a mouth and an anus.
B
18. While looking at some seawater through your microscope, you spot the egg of an unknown animal. Which of the following tests could you use to determine whether the developing organism is a protostome or a deuterostome? See whether the embryo _____. A) develops germ layers B) exhibits spiral cleavage or radial cleavage C) develops a blastopore D) develops an archenteron
B
18. While sampling marine plankton in a lab, a student encounters large numbers of fertilized eggs. The student rears some of the eggs in the laboratory for further study and finds that the blastopore becomes the mouth. The embryo develops into a trochophore larva and eventually has a true coelom. These eggs probably belonged to a(n) _____. A) echinoderm B) mollusc C) nematode D) arthropod
B
2. Which of the following is (are) unique to animals? A) the structural carbohydrate, chitin B) nervous system signal conduction and muscular movement C) heterotrophy D) flagellated gametes
B
22. Among protostomes, which morphological trait has shown the most variation? A) type of symmetry (bilateral vs. radial vs. none) B) type of body cavity (coelom vs. pseudocoelom vs. no coelom) C) number of embryonic tissue types (diploblasty vs. triploblasty) D) type of development (protostome vs. deuterostome)
B
28. If we were to separate these eight cells and attempt to culture them individually, then what is most likely to happen? A) All eight cells will die immediately. B) Each cell may continue development, but only into a nonviable embryo that lacks many parts. C) Each cell may develop into a full-sized, normal embryo. D) Each cell may develop into a smaller-than-average, but otherwise normal, embryo.
B
28. What would be the most effective method of reducing the incidence of blood flukes in a human population? A) reduce the mosquito population B) reduce the population of the intermediate snail host C) avoid contact with rodent droppings D) carefully wash all raw fruits and vegetables
B
3. The larvae of some insects are merely small versions of the adult, whereas the larvae of other insects look completely different from adults, eat different foods, and may live in different habitats. Which of the following is most directly involved in the evolution of these variations in metamorphosis? A) artificial selection of sexually immature forms of insects B) changes in the homeobox genes governing early development C) the evolution of meiosis D) the origin of a brain
B
30. We should expect the inner wall of the swim bladder to be lined with tissue that is derived from _____. A) ectoderm B) endoderm C) mesoderm D) mesoglea
B
35. Suppose a researcher for a pest-control company developed a chemical that inhibited the development of an embryonic mosquito's endodermal cells. Which of the following would be a likely mechanism by which this pesticide works? A) The mosquito would develop a weakened exoskeleton that would make it vulnerable to trauma. B) The mosquito would have trouble digesting food, due to impaired gut function. C) The mosquito would have trouble with respiration and circulation, due to impaired muscle function. D) The mosquito wouldn't be affected at all.
B
37. You find a multi-legged animal in your garden and want to determine if it is a centipede or a millipede. You take the animal to a university where a myriapodologist quickly tells you that you have found a centipede. Which of the following may have allowed her to make this distinction? A) segmentation B) poisonous fangs C) egg-laying D) molting
B
38. Whiteflies are common pest insects found on cotton, tomato, poinsettia, and many other plants. Nymphs are translucent and mostly sessile, feeding on their host plants' phloem (sap) from the undersides of leaves. They undergo incomplete metamorphosis into winged adults. Because whitefly nymphs cannot escape predation by moving, you hypothesize that their translucent bodies make them hard to spot by predators. How could you directly test this hypothesis? A) Compare rates of predation on whitefly nymphs on plant leaves of different colors (for example, red vs. green poinsettia leaves). B) Compare rates of predation on whitefly nymphs coated with a nontoxic dye vs. undyed whitefly nymphs. C) Compare rates of predation on whitefly nymphs vs. whitefly adults. D) Compare rates of predation on whitefly nymphs by predators that are translucent vs. predators that are not translucent.
B
39. Fossil evidence indicates that the following events occurred in what sequence, from earliest to most recent? 1. Protostomes invade terrestrial environments. 2. Cambrian explosion occurs. 3. Deuterostomes invade terrestrial environments. 4. Vertebrates become top predators in the seas. A) 2 → 1 → 4 → 3 B) 2 → 4 → 1 → 3 C) 2 → 3 → 1 → 4 D) 2 → 1 → 3 → 4
B
42. How would a terrestrial centipede most likely benefit from the ability to close its spiracles? Closing spiracles would _____. A) allow the centipede to move more quickly B) allow the centipede to retain more moisture in its tissues C) allow the centipede to stay warmer D) allow more oxygen from the environment to reach the centipede's tissues
B
5. Both animals and fungi are heterotrophic. What distinguishes animal heterotrophy from fungal heterotrophy is that most animals derive their nutrition by _____. A) preying on animals B) ingesting it C) consuming living, rather than dead, prey D) using enzymes to digest their food
B
50. The spiracles and tracheae of insects have a function most similar to that of _____. A) rhinophores B) dorsal plummules C) cerata. D) chemoreceptors
B
55. The water vascular system of echinoderms _____. A) functions as a circulatory system that distributes nutrients to body cells B) functions in locomotion and feeding C) is bilateral in organization, even though the adult animal is not bilaterally symmetrical D) is analogous to the gastrovascular cavity of flatworms
B
6. Which of the following Tp traits is different from all other known animals? A) Tp is multicellular. B) Tp lacks muscle and nerve cells. C) Tp has cilia. D) Tp lacks cell walls.
B
A student encounters an animal embryo at the eight-cell stage. The four smaller cells that comprise one hemisphere of the embryo seem to be rotated 45 degrees and to lie in the grooves between larger, underlying cells. 27. This embryo may potentially develop into a(n) _____. A) turtle B) earthworm C) sea star D) sea urchin
B
Healthy corals are brightly colored because they _____. A) secrete colorful pigments to attract mates B) host symbionts with colorful photosynthetic pigments C) build their skeletons from colorful minerals D) secrete colorful pigments to protect themselves from ultraviolet light
B
In terms of food capture, which sponge cell is most similar to the cnidocyte of a cnidarian? A) amoebocyte B) choanocyte C) epidermal cell D) pore cell
B
10. The evolution of animal species has been prolific (the estimates go into the millions and tens of millions). Much of this diversity is a result of the evolution of novel ways to _____. A) reproduce B) arrange cells into tissues C) sense, feed, and move D) form an embryo and establish a basic body plan
C
14. Which of the following genetic processes may be most helpful in accounting for the Cambrian explosion? A) binary fission B) random segregation C) gene duplication D) chromosomal condensation
C
15. Whatever its ultimate cause(s), the Cambrian explosion is a prime example of _____. A) mass extinction B) evolutionary stasis C) adaptive radiation D) a large meteor impact
C
19. Which structure do sea slugs use to feed on their prey? A) nematocysts B) an incurrent siphon C) a radula D) a mantle cavity
C
20. Which of the following is a feature of the tube-within-a-tube body plan in most animal phyla? A) The outer tube consists of a hard exoskeleton. B) The outer tube consists of digestive organs. C) The mouth and anus form the ends of the inner tube. D) The two "tubes" are separated by tissue that comes from embryonic endoderm.
C
22. If the dinoflagellate-containing sea slug P. ianthina preys on coral animals, then it would be LEAST surprising to find that _____. A) P. ianthina has no tolerance to the toxin in the nematocysts of its prey B) P. ianthina can locate its coral prey by chemicals released into the water by corals C) the coral prey harbor dinoflagellates in their tissues D) the coral prey transform themselves into medusas to flee from approaching P. ianthina
C
24. Soon after the coelom begins to form, a researcher injects a dye into the coelom of a deuterostome embryo. Initially, the dye should be able to flow directly into the _____. A) blastopore B) blastocoel C) archenteron D) pseudocoelom
C
25. A natural predator of the crown-of-thorns sea star is a mollusc called the Giant Triton, Charonia tritonis. If the triton uses a radula to saw into the sea star, then to which clade should the triton belong? A) chitons B) bivalves C) gastropods D) cephalopods
C
26. On the basis of information in the paragraph above, which of these should be able to be observed in Tp? A) the act of fertilization B) the process of gastrulation C) eggs D) All three of the listed responses are correct.
C
32. The protostome developmental sequence arose just once in evolutionary history, resulting in two main subgroups—Lophotrochozoa and Ecdysozoa. What does this finding suggest? A) These two subgroups have a common ancestor that was a deuterostome. B) The protostomes are a polyphyletic group. C) Division of these two groups occurred after the protostome developmental sequence appeared. D) The lophotrochozoans are monophyletic.
C
32. Which characteristic is shared by cnidarians and flatworms? A) dorsoventrally flattened bodies B) radial symmetry C) a digestive system with a single opening D) a distinct head
C
34. Parasitism is one of the most widespread life strategies ever to evolve. Which of the following is consistent with this finding? A) Parasites almost always predigest their hosts' tissues and, therefore, spend less energy and require fewer structural adaptations. B) Parasites, unlike predators, feed on almost all the tissues of their host. C) Parasites do not generally kill their hosts; thus they can feed on the same host throughout the host's normal life span and do not have competition from decomposers. D) Parasites generally kill their host and can feed for a very long time because they are much smaller than their host.
C
36. Arthropod exoskeletons and mollusk shells both _____. A) completely replace the hydrostatic skeleton B) are secreted by the mantle C) help retain moisture in terrestrial habitats D) are comprised of the polysaccharide chitin
C
38. If nudibranch rhinophores are located at the anterior ends of these sea slugs, then they contribute to the sea slugs' _____. A) segmentation B) lack of torsion C) cephalization D) identity as lophotrochozoans
C
39. All arthropods _____. 1) undergo complete metamorphose 2) have jointed appendages 3) molt 4) have segmented bodies 5) have an exoskeleton or cuticle A) 1, 2, and 4 B) 3 and 5 C) 2, 3, 4, 5 D) 1, 4, 5
C
4. As you are on the way to Tahiti for a vacation, your plane crash-lands on a previously undiscovered island. You soon find that the island is teeming with unfamiliar organisms, and you, as a student of biology, decide to survey them (with the aid of the Insta-Lab Portable Laboratory you brought along in your suitcase). You select three organisms and observe them in detail, making the notations found in the figure above. Which organism would you classify as an animal? A) organism A B) organism B C) organism C
C
4. Which of the following can be found in the mesohyl of a sponge? 1. amoebocytes 2. spicules 3. spongin 4. zygotes 5. choanocytes A) 1 and 2 B) 2, 3, 4 C) 1, 2, 3, and 4 D) 1, 2, 3, 4, and 5
C
40. Look at the graph for Cormocephalus morsitans in the figure above. What is the best interpretation of these results? A) The centipede had its spiracles open the entire time. B) The centipede had its spiracles closed the entire time. C) The centipede had its spiracles open when carbon dioxide (CO2) emission peaked and closed when CO2 emission was low. D) The centipede had its spiracles closed when carbon dioxide (CO2) emission peaked and open when CO2 emission was low.
C
41. The most ancient branch point in animal phylogeny is the characteristic of having _____. A) radial or bilateral symmetry B) diploblastic or triploblastic embryos C) true tissues or no tissues D) a body cavity or no body cavity
C
48. The claws (fangs) on the foremost trunk segment of centipedes have a function most similar to that of _____. A) rhinophores B) dorsal plummules C) cerata D) chemoreceptors
C
49. The stingers of honeybees have a function most similar to that of _____. A) rhinophores B) dorsal plummules C) cerata D) chemoreceptors
C
57. Which of the following animal groups is entirely aquatic? A) Mollusca B) Crustacea C) Echinodermata D) Nematoda
C
6. Most cnidarians are known to produce toxins. In fact, it has been claimed that one particular species produces the most deadly of all toxins on the planet. What feature of this group most likely evolved simultaneously with the evolution of these toxins? A) the medusa body form B) asexual reproduction C) a slow-moving or sessile lifestyle in the adult D) diploblastic design
C
9. The crown-of-thorns sea star, Acanthaster planci, preys on the flesh of live coral. If coral animals are attacked by these sea stars, then what actually provides nutrition to the sea star, and which chemical (besides the toxin within their nematocysts) do the corals rely on for protection? A) medusae; silica B) exoskeleton; calcium carbonate C) polyps; calcium carbonate D) polyps; silica
C
Nematodes and arthropods both _____. A) develop an anus from the blastopore (pore) formed in the gastrula stage B) are suspension feeders C) grow by shedding their exoskeleton D) have ciliated larvae
C
10. One day, Tommy, a student in an undersupervised class of forty fifth graders, got the urge to pet Nemo (the clownfish), who was swimming among the waving petals of a pretty underwater "flower" that had a big hole in the midst of the petals. Tommy giggled upon finding that these petals felt sticky. A few hours later, Tommy was in the nurse's office with nausea and cramps. Microscopic examination of his fingers would probably have revealed the presence of ______. A) teeth marks B) spines C) spicules D) nematocysts
D
11. The last common ancestor of all animals was probably a _____. A) unicellular chytrid B) multicellular algae C) multicellular fungus D) flagellated protist
D
11. The teacher and class were especially saddened when the colonial hydrozoan died. They had watched it carefully, and the unfortunate creature never even got to produce offspring by budding. Yet, everyone was elated when one of the students noticed a small colonial hydrozoan growing in a part of the tank far from the location of the original colony. The teacher was apparently unaware that these hydrozoans exhibit _____. A) spontaneous generation B) abiogenesis C) alternation of generations D) a medusa stage
D
13. The presence of a lophophore in a newly discovered species would suggest that the species _____. A) has an exoskeleton B) grows by shedding its external covering C) is motile D) is a suspension feeder
D
13. Which statement is most consistent with the hypothesis that the Cambrian explosion was caused by the rise of predator-prey relationships? The fossil record reveals an increased incidence of _____. A) worm burrows B) larger animals C) organic material D) hard parts
D
15. What would be the best anatomical feature to look for to distinguish a gastropod from a chiton? A) presence of a muscular foot B) presence of a rasp-like feeding structure C) production of eggs D) number of shell plates
D
16. Arthropods invaded land about 100 million years before vertebrates did so. This most clearly implies that _____. A) arthropods evolved before vertebrates did B) extant terrestrial arthropods are better adapted to terrestrial life than are extant terrestrial vertebrates C) vertebrates evolved from arthropods D) arthropods have had more time to coevolve with land plants than have vertebrates
D
16. Which of the following organisms would you expect to have the largest surface-area-to- volume ratio? Assume that all of the following are the same total length. A) a mollusk B) an annelid C) an arthropod D) a platyhelminth
D
17. Against which hard structure do the circular and longitudinal muscles of annelids work? A) cuticle B) shell C) endoskeleton D) hydrostatic skeleton
D
19. In examining an unknown animal species during its embryonic development, how can you be sure what you are looking at is a protostome and not a deuterostome? A) There is evidence of cephalization. B) The animal is triploblastic. C) The animal is clearly bilaterally symmetrical. D) You see a mouth, but not an anus.
D
23. The sea slug Elysia chorotica has no nematocysts or dinoflagellates but, rather, has "naked" chloroplasts in its skin. The chloroplasts are all that remain of the seaweed (Vaucheria sp.) that Elysia feeds upon. The chloroplasts are transferred to the skin; consequently, this slug is green. It spends most of its time basking in shallow water on the surface of seaweeds. How should we expect its chloroplasts to benefit the Elysia sea slug? 1. provide Elysia with fixed carbon dioxide 2. provide Elysia with fixed nitrogen 3. provide Elysia with protective coloration A) 1 only B) 2 only C) 3 only D) 1 and 3
D
23. What do all deuterostomes have in common? A) Adults are bilaterally symmetrical. B) Embryos have pharyngeal pouches that may or may not form gill slits. C) All have a spinal column. D) The pore (blastopore) formed during gastrulation becomes the anus.
D
25. You have before you a living organism, which you examine carefully. Which of the following should convince you that the organism is acoelomate? A) It is triploblastic. B) It has bilateral symmetry. C) It possesses sensory structures at its anterior end. D) Muscular activity of its digestive system distorts the body wall.
D
26. If the teacher wanted to show the students what a lophophore is and how it works, the teacher would point out a feeding _____. A) hydra B) sponge C) gastropod D) ectoproct
D
27. The teacher was unaware of the difference between suspension feeding and predation. The teacher thought that providing live copepods (2 mm long) and feeder fish (2 cm long) would satisfy the dietary needs of all of the organisms. Consequently, which two organisms would have been among the first to starve to death (assuming they lack photosynthetic endosymbionts)? A) sponges and corals B) sea stars and sponges C) shrimp and bivalves D) bivalves and sponges
D
37. Cycliophorans have two types of larvae. One type of larva is produced when the digestive system of a female is impregnated by a male. The digestive system then collapses and develops into a larva, which swims away in search of a new host after the surrounding female dies. Which is the embryonic tissue that is apparently most important in forming this type of larva? A) mesohyl B) mesoderm C) ectoderm D) endoderm
D
42. You find a new species of worm and want to classify it. Which of the following lines of evidence would allow you to classify the worm as a nematode and not an annelid? A) It is segmented. B) It is triploblastic. C) It has a coelom. D) It sheds its external skeleton to grow.
D
43. Compare the graphs in the figure above of carbon dioxide (CO2) emission for Cormocephalus morsitans and Scutigerina weberi. What hypothesis can you make about each centipede's habitat? A) C. morsitans lives in a habitat that provides more carbon dioxide than does S. weberi. B) C. morsitans lives in a habitat with more predators than does S. weberi. C) C. morsitans lives in a colder habitat than does S. weberi. D) C. morsitans lives in a drier habitat than does S. weberi.
D
44. What would be the most direct effect of removing or damaging an insect's antennae? The insect would have trouble _____. A) hearing B) mating C) seeing D) smelling
D
46. A terrestrial animal species is discovered with the following larval characteristics: exoskeleton, system of tubes for gas exchange, and modified segmentation. A knowledgeable zoologist should predict that the adults of this species would also feature _____. A) eight legs B) two pairs of antennae C) a sessile lifestyle D) an open circulatory system
D
5. Which of the following factors, when used to label the horizontal axis of the graph above, would account most directly for the shape of the plot? A) rate of cribrostatin synthesis (molecules/unit time) B) number of pores per sponge C) number of spicules per sponge D) number of choanocytes per sponge
D
52. If the pond organisms are larvae, rather than adults, Sarah should expect them to have all of the following structures, EXCEPT _____. A) antennae B) an open circulatory system C) an exoskeleton of chitin D) sex organs
D
54. As you are walking along a beach, you find an animal and believe that it belongs to the class Asteroidea. Which of the following characteristics would support your hypothesis that the animal is a sea star and not another type of echinoderm? A) It is pentaradially symmetric. B) It feeds on other animals. C) It has a hydrostatic skeleton, formed from its water vascular system. D) Its central region is not well-delineated from its appendages.
D
7. What do animals ranging from corals to monkeys have in common? A) a mouth and an anus B) number of embryonic tissue layers C) type of body symmetry D) presence of Hox genes
D
9. Which of the following would you classify as something other than an animal? A) sponges B) coral C) jellyfish D) choanoflagellates
D