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

8) Use the information to answer the question.

Trichoplax adhaerens 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 2,000 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. Individual animals move using cilia, and any "edge" can lead. T. adhaerens 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. T. adhaerens sperm cells have never been observed, nor have embryos past the 64-cell (blastula) stage.

Which of the following T. adhaerens traits is different from all other known animals?

A) T. adhaerens is multicellular.
B) T. adhaerens lacks muscle and nerve cells.
C) T. adhaerens has cilia.

D) T. adhaerens lacks cell walls.

B

7) 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 materials

C) consuming living, rather than dead, prey
D) using enzymes to digest their food

B

10) 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 descendants of such adults

A

11) The fact that choanoflagellates and collar cells of sponges resemble each other supports the inference that ________.
A) choanoflagellates are animals
B) choanoflagellates are more closely related to sponges than they are to protists

C) choanoflagellates and sponges are sister groups
D) choanoflagellates and sponges evolved similar cell structures through convergent evolution

C

12) Which of the following would you classify as something other than an animal?

A) sponge
B) coral
C) jellyfish

D) choanoflagellate

D

13) The evolution of animal species has been prolific (current estimates of species numbers reach into the 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) The last common ancestor of all animals was probably a ________.

A) unicellular chytrid
B) multicellular algae
C) multicellular fungus

D) flagellated protist

D

19) Arthropods invaded land about 100 million years before vertebrates. This fact 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

22) 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

23) 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

24) 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

25) 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

27) Among protostomes, which morphological trait has shown the most variation?

A) type of symmetry (bilateral versus radial versus none)
B) type of body cavity (coelom versus pseudocoelom versus no coelom)
C) number of embryonic tissue types (diploblasty versus triploblasty)

D) type of development (protostome versus deuterostome)

B

28) 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

32) A student encounters an animal embryo at the eight-cell stage. The four smaller cells that comprise 1 hemisphere of the embryo seem to be rotated 45° and to lie in the grooves between larger, underlying cells. This embryo may potentially develop into a(n) ________.
A) turtle

B) earthworm
C) sea star
D) sea urchin

B

35) 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

36) Which of these statements, if accurate, would support the claim that the ancestral cnidarians had bilateral symmetry?
A) Cnidarian larvae possess anterior-posterior, left-right, and dorsal-ventral aspects.
B) Cnidarians have fewer Hox genes than bilaterians.

C) All cnidarians are acoelomate.
D) The presence of collar cells.

A

41) What is the probable sequence in which the following animal clades originated, from earliest to most recent?
A) bilaterians, deuterostomes, vertebrates, tetrapods, amniotes
B) bilaterians, deuterostomes, amniotes, vertebrates, tetrapods

C) deuterostomes, bilaterians, amniotes, vertebrates, tetrapods D) deuterostomes, bilaterians, vertebrates, tetrapods, amniotes

A

42) 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

43) When a scientist describes the "body plan" of a phylum, he or she is implying that ________.

A) organisms direct their own evolution in order to maximize their success
B) animals evolve according to a pre-ordained plan
C) the body shapes we see now have been more successful than others in the past

D) mutations have arisen that allow only some shapes to be produced

C

44) Which of the following statements comparing symmetry in sessile and swimming animals is most probable?
A) Radial symmetry is more advantageous for active swimming than is bilateral symmetry.
B) Radial symmetry occurs most frequently in animals that catch their prey by rapid swimming.

C) Bilateral symmetry allowed animals to evolve nerves.

D) Bilaterally symmetric animals can be streamlined for swimming, but radially symmetric animals cannot.

D

46) Nine-banded armadillos give birth to four offspring at a time. An amazing fact about these offspring is that they are genetically identical to each other. This fact suggests ________.
A) the young undergo metamorphosis
B) the embryo undergoes radial and indeterminate cleavage

C) the first cell division of the fertilized egg is perpendicular to the vertical axis of the egg

D) the species is pseudocoelomate

B

47) 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

48) The common ancestor of the protostomes had a coelom. What does this suggest?

A) All lophotrochozoans have a coelom.
B) There are no pseudocoelomates within the protostomes.
C) There are no acoelomates within the protostomes.

D) The body cavity evolved before the lophophore.

D

1) One of the characteristics unique to animals is

A) gastrulation.
B) multicellularity.
C) sexual reproduction.

D) flagellated sperm.

A

2) The distinction between sponges and other animal phyla is based mainly on the absence versus the presence of
A) a body cavity.
B) a complete digestive tract.

C) mesoderm.
D) tissues.

D

63) Placing sponges as the basal metazoans on the basis of lack of tissues implies which of the following?
A) Sponge ancestors never had tissues.
B) Modern-day sponges have lost the ability to form tissues.

C) Multicellular, modern-day choanoflagellates can form tissues.

D) Sponges do not have nerve cells.

A

18) 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 filter feeder

D

9) 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

21) 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 mollusc
B) an annelid

C) an arthropod
D) a platyhelminth

D

23) 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

35) 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

36) 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

38) Molecular studies have changed many of the phylogenetic relationships previously identified by morphological studies. An example of such a change is ________.
A) Lochotrophozora
B) Placozoa

C) Brachiopoda
D) Bivalvia

A

40) Large animals need specialized organs for gas exchange because ________.

A) they require more oxygen per unit of volume
B) surface area increases more rapidly than volume as size increases
C) volume increases more rapidly than surface area as size increases

D) they collect more energy and therefore have more energy to allocate to specialized tissues

C

44) Which of the following changes would lead to an increase in surface-area-to-volume ratios?

A) thickening of the body of earthworms
B) increasing the number of layers in the chloroplasts of plants
C) decreasing the projections of the choanocytes of sponges on the outer surface of the body

D) reducing the branching of the mesoderm tissues of sponges

B

47) Nematodes and arthropods both ________.
A) develop an anus from the blastopore (pore) formed in the gastrula stage

B) are parasites
C) grow in conjunction with shedding of their exoskeleton
D) have ciliated larvae

C

51) All insects ________.
A) undergo complete metamorphosis and have segmented bodies
B) have jointed appendages and a radula
C) undergo complete metamorphosis and have an exoskeleton or cuticle

D) have jointed appendages and spicules

C

57) 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

C

58) 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

59) 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

72) 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

73) 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

74) Which of the following animal groups is entirely aquatic?

A) Mollusca
B) Crustacea
C) Echinodermata

D) Nematoda

C