until that gas arrives at the
A) mouth.
B) gills.
C) skin.
D) heart.
E) anus.
63) Which shark structure is most analogous to a swim bladder full of gas?
A) its lateral line system
B) its spiral valve
C) its liver
D) its dead-end nostrils
E) its gills
64) When a shark stops swimming, it does which of the following?
1. sinks
2. quickly dies
3. oxygenates its blood less effectively
A) 1 only
B) 2 only
C) 3 only
D) 1 and 3
E) 1, 2, and 3
65) 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.
E) neurectoderm.
66) Regarding its position in the water column, the same thing that happens to a shark when it stops
swimming also happens to a
A) physostomus fish when it gulps air.
B) physoclistus fish when it moves gas from the blood into the water.
C) physoclistus fish when it moves gas from the swim bladder into the blood.
D) physoclistus fish when it moves gas from the blood into the swim bladder.
67) In coelacanths, a swim bladder is present, but the swim bladder is full of adipose tissue (fat), which
is there on a fairly permanent basis. If such a swim bladder is used by coelacanths to affect buoyancy,
then it does so in much the same way as does the
A) liver of a shark.
B) physoclistus swim bladder.
C) physostomus swim bladder.
D) lung of a lungfish.
68) Which graph properly depicts the relationship between the amount of gas in the swim bladder and
the density of the fish?
A)
B)
C)
D)
E)
69) If a ray-finned fish is to both hover (remain stationary) in the water column and ventilate its gills
effectively, then what other structure besides its swim bladder will it use?
A) its heart
B) its pectoral fins
C) its lateral line system
D) its caudal (tail) fin
E) its opercula
70) Which graph below best represents the way that density changes over time in a physoclistus fish and
in a physostomus fish, respectively?
A)
B)
C)
D)
A) A and B
B) B and A
C) B and C
D) C and B
E) D and B
71) At 5, 10, and 15 hours in the graph below, which of the following statements should be true?
A) This fish is in the process of adding gas to its swim bladder.
B) This fish is in the process of removing gas from its swim bladder.
C) This fish has a swim bladder that is relatively full of gas.
D) This fish has a swim bladder that contains relatively little gas.
The following questions refer to the phylogenetic tree shown in Figure 34.2.
Figure 34.2
72) Which number represents the birds?
A) 3
B) 4
C) 6
D) 8
E) 10, if it were at the end of a branch emerging from the dinosaurs
73) Which pair of numbers represents extinct reptiles that had returned to an aquatic life?
A) 1 and 2
B) 3 and 4
C) 5 and 7
D) 6 and 8
E) 7 and 9
74) If circle 3 includes all of the extant reptiles that are ectotherms, then what do circles 4 and 6
represent?
A) crocodiles and birds
B) turtles and birds
C) ratites and carinates
D) mammals and birds
E) There is not enough information to say.
75) Which number represents the closest relative to the parareptiles?
A) 1
B) 2
C) 3
D) 9
E) It is not possible to say.
76) Which of these numbers represents ectotherms that were able to fly?
A) 1
B) 2
C) 7
D) 8
E) It is not possible to say.
77) Whose DNA would have had the most sequence homologies with amphibian DNA?
A) 5
B) 6
C) 7
D) 8
E) 9
78) In order for the four-chambered hearts of birds and mammals to be homologous, which other
organisms would have to have had four-chambered hearts?
A) dinosaurs
B) thecodonts
C) plesiosaurs
D) synapsids
E) stem reptiles
79) The organisms represented by number 8 are
A) birds.
B) mammals.
C) nonbird, terrestrial reptiles.
D) aquatic reptiles.
E) all mammals except humans.
Scenario Questions
The following questions refer to the description below.
Terry catches a ray-finned fish from the ocean and notices that attached to its flank is an equally long,
snakelike organism. The attached organism has no external segmentation, no scales, a round mouth
surrounded by a sucker, and two small eyes. Terry thinks it might be a marine leech, a hagfish, or a
lamprey.
80) Which feature excludes the organism from possibly being a leech?
A) elongated shape
B) lack of scales
C) lack of external segmentation
D) round mouth
E) anterior sucker
81) Terry detaches the snakelike organism from the fish and uses a knife to cut off its head. In doing so,
its brain slides out onto the deck of the boat. Terry peers into the cut end of the head and notices that the
brain had lain in a sort of panlike structure that only partially surrounded the brain. What is the structure
Terry is observing, and what is it made of?
A) skull, made of bone
B) cranium, made of bone
C) cranium, made of cartilage
D) vertebral column, made of bone
E) vertebral column, made of cartilage
82) Terry takes the body of the snakelike organism and slices it open along its dorsal side. If it is a
hagfish, what should Terry see?
A) a well-developed series of bony vertebrae surrounding the spinal cord
B) a well-developed series of cartilaginous vertebrae surrounding the spinal cord
C) a tube of cartilage (surrounding the notochord) with dorsal projections on both sides of the spinal
cord
D) a notochord, located underneath the spinal cord
83) The snakelike organism turned out to be a hagfish. Consequently, why should Terry throw the fish
to which the hagfish was attached overboard, rather than having it for dinner?
A) It has mucus on its skin.
B) If it had an ectoparasite, then it must also have endoparasites.
C) The bite of the hagfish introduces paralytic neurotoxins, which Terry wants to avoid.
D) It was already sick or dying; otherwise, the hagfish would probably not have attacked it.
84) Having caught and handled a hagfish, what will Terry’s shipmates most likely require Terry to do
before returning to further fishing?
A) Wash his hands and then don gloves to prevent the spread of harmful microbes that live only on
hagfish skin.
B) Clean the bucketsful of hagfish slime from the deck of the boat.
C) Dispose of the fishing tackle that had been poisoned by coming into contact with the hagfish.
D) Cut up the remaining hagfish and share pieces of this highly sought-after baitfish.
85) Terry saved some of the tooth-like objects within the hagfish’s round mouth to analyze their
composition in his mentor’s biochemistry research lab. Terry will find that they are composed of the
same protein found in tetrapod
A) skin.
B) teeth.
C) bones.
D) cartilage.
E) muscles.
The following questions refer to the description below.
While on an intersession course in tropical ecology, Kris pulls a large, snakelike organism from a
burrow (the class was granted a collecting permit). The 1-m-long organism has smooth skin, which
appears to be segmented. It has two tiny eyes that are hard to see because they seem to be covered by
skin. Kris brings it back to the lab at the field station, where it is a source of puzzlement to the class.
Kris says that it is a giant oligochaete worm; Shaun suggests it is a legless amphibian; Kelly proposes it
belongs to a snake species that is purely fossorial (lives in a burrow).
86) The class decided to humanely euthanize the organism and subsequently dissect it. Having decided
that it was probably not a reptile, two of their original hypotheses regarding its identity remained. Which
of the following, if observed, should help them arrive at a conclusive answer?
A) presence of a closed circulatory system
B) presence of moist, highly vascularized skin
C) presence of lungs
D) presence of a nerve cord
E) presence of a digestive system with two openings
87) The organism was found to have two lungs, but the left lung was much smaller than the right lung.
Kelly added that the herpetology instructor had said that in most snakes, the same condition exists. If the
size difference between the lungs in this organism is not a shared ancestral characteristic with its
occurrence in snakes, then its existence in this organism is explained as which of the following?
1. a result of convergent evolution
2. an example of homologous structures
3. a similar adaptation to a shared lifestyle or body plan
4. a result of having identical Hox genes
5. a homoplasy
A) 3 only
B) 1 and 5
C) 1, 3, and 5
D) 2, 3, and 5
E) 3, 4, and 5
88) The adaptation of the body shape of snakes has resulted in one of their lungs becoming vestigial.
Another adaptation (to a fossorial lifestyle) is snakes’ absence of limbs. If the “mystery organism” has
also become adapted to a fossorial lifestyle, though its ancestors moved about on the surface, then which
structures should one expect to find upon dissecting the organism?
1. reduced or absent pelvic and/or pectoral girdles
2. metanephridia
3. hydrostatic skeleton
A) 1 only
B) 1 and 2
C) 1 and 3
D) 2 and 3
E) 1, 2, and 3
89) Which one of these, if found, should clear up any remaining doubt as to the identity of the
organism?
A) vestigial pelvic girdle
B) blood vessels carrying oxygenated blood from both the skin and the functional lung to the heart
C) closed circulatory system
D) ability to produce toxins from glands located on the skin, or that empty into the mouth
E) two-chambered heart
Due to its system of nine air sacs connected to the lungs, the respiratory system of birds is arguably the
most effective respiratory system of all air-breathers. Upon inhalation, air first flows into posterior air
sacs, then into the lungs, and then into anterior air sacs on the way to being exhaled. Thus, there is one-
way flow of air through the lungs, along thousands of tubules called parabronchi.
90) If the inner lining of the air sacs is neither thin nor highly vascularized, then what can be inferred
about the air sacs?
A) They must not belong to the respiratory system.
B) They cannot be derived from endoderm.
C) They cannot be sites of gas exchange between air and blood.
D) They must obtain nutrition from some source other than the bloodstream.
E) They cannot effectively moisturize the air before it reaches the lungs.
91) Some bird bones are hollow rather than honeycombed. The hollow bones mostly contain air sacs.
The replacement of bone marrow with air sacs is properly understood as an adaptation to
A) reduce the weight of the bird.
B) facilitate flight.
C) eliminate the functions that marrow performs.
D) All three of the options listed are correct.
E) Only two of the options listed are correct.
92) Birds generate a lot of heat, especially during flight. Yet the adipose tissue under their skin and the
feathers atop their skin make it difficult to eliminate excess heat across the skin. Which of the following
alternatives can absorb body heat and eliminate it from the bird most effectively?
A) air in the air sacs
B) lymph in the lymphatic vessels
C) blood in the vessels
D) blood in the heart
E) urine in the bladder
93) If Archaeopteryx had air sacs, then which of its features would have had the opposite effect on
enabling Archaeopteryx to fly long distances from that provided by air sacs?
1. teeth
2. contour feathers
3. wing claws
4. long tail with many vertebrae
A) 1 and 2
B) 1 and 4
C) 2 and 3
D) 1, 2, and 4
E) 1, 3, and 4
94) Which feature of some carinates has the same effect on weight as the presence of air sacs?
A) presence of a large, heavily keratinized beak
B) absence of a urinary bladder
C) presence of a carina (keel)
D) number of chambers in the heart
E) presence of large pectoral muscles
95) The movement of air along parabronchi is most similar to the movement of
A) air in the lungs of other amniotes.
B) food/waste in a gastrovascular cavity.
C) food/waste in a digestive system with separate mouth and anus.
D) the frog tongue during feeding.
E) air in lungs of terrestrial amphibians.
96) Which type of bird is most likely to need air sacs to reduce its weight?
A) birds that migrate long distances
B) waterfowl that float on water, but do not dive
C) birds that spend much of their time underwater
D) ratites
97) The one-way flow of air along parabronchi makes what type of exchange mechanism possible, at
least theoretically?
A) the same as that occurring in fish gills
B) the same as that occurring in insect tracheae
C) the same as that occurring in mammalian lungs
D) the same as that occurring in echinoderm skin gills
In the United States and Canada, bats use one of two strategies to survive winter: They either migrate
south, or they hibernate. Recently, those that hibernate seem to have come under attack by a fungus,
Geomyces destructans (Gd), an attack that is occurring from Missouri to southern Canada. Many
infected bats have a delicate, white filamentous mat on their muzzles, which is referred to as white-nose
syndrome (WNS). The fungus invades the bat tissues, causes discomfort, and awakens the bat from its
hibernation. The bat fidgets and wastes calories, using up its stored fat. The bat then behaves
abnormally, leaving its cave during daytime in winter to search for food. Their food, primarily insects, is
scarce during the winter, and the bats ultimately starve to death. Since 2007, it is estimated that up to 1
million bats have perished from WNS.
98) The Gd mat on the fur of the bats should be expected to consist of
A) hyphae.
B) haustoria.
C) arbuscules.
D) yeasts.
E) basidia.
99) Gd is a cold-loving fungus. Thus, which characteristics of normal bat behavior can be most expected
to favor the growth of this fungus?
A) southward migration during the winter
B) communal roosting in tightly packed clusters during hibernation
C) reliance on fat reserves for calories during hibernation
D) much-reduced metabolic rate during hibernation
E) hibernating in parts of the cave that are farthest away from the mouth of the cave
100) Gd is a cold-loving fungus. Thus, which characteristics of abnormal bat behavior can be most
expected to favor the growth of this fungus?
A) shifting roosting location to the mouth of the cave during winter
B) searching for food during winter
C) searching for food during the day
D) All three of the options listed are correct.
E) Only two of the options listed are correct.
101) Gd is a cold-loving fungus. Thus, which characteristics of normal bat behavior can be most
expected to favor the spread of this fungus to uninfected bats?
A) southward migration during the winter
B) communal roosting in tightly packed clusters during hibernation
C) reliance on fat reserves for calories during hibernation
D) much-reduced metabolic rate during hibernation
E) hibernating in parts of the cave that are farthest away from the mouth of the cave
102) Almost all North American bats are insectivores, with one notable exception being a bat that bites
and then laps blood from the wound. The blood-lapping bats are limited to the warm, southwestern
United States. Thus, if WNS continues to decimate bat populations in the United States and Canada,
then we can expect
A) livestock bites from vampire bats to increase in frequency.
B) plant diseases that are spread by insects to increase in frequency.
C) plant diseases directly caused by insect feeding to increase in frequency.
D) human and livestock diseases that are spread by insects to increase in frequency.
E) all but one of these are correct.
103) Which feature(s) allow(s) hibernating bats to conserve heat without using calories?
A) shivering
B) fur
C) fat layer below the skin
D) All three of the options listed are correct.
E) Two of the options listed are correct.
End-of-Chapter Questions
The following questions are from the end-of–chapter “Test Your Understanding” section in Chapter 34
of the textbook.
104) Vertebrates and tunicates share
A) jaws adapted for feeding.
B) a high degree of cephalization.
C) the formation of structures from the neural crest.
D) an endoskeleton that includes a skull.
E) a notochord and a dorsal, hollow nerve cord.
105) Some animals that lived 530 million years ago resembled lancelets but had a brain and a skull.
These animals may represent
A) the first chordates.
B) a “missing link” between urochordates and cephalochordates.
C) early craniates.
D) marsupials.
E) nontetrapod gnathostomes.
106) Which of the following could be considered the most recent common ancestor of living tetrapods?
A) a sturdy-finned, shallow-water lobe-fin whose appendages had skeletal supports similar to those of
terrestrial vertebrates
B) an armored, jawed placoderm with two pairs of appendages
C) an early ray-finned fish that developed bony skeletal supports in its paired fins
D) a salamander that had legs supported by a bony skeleton but moved with the side-to-side bending
typical of fishes
E) an early terrestrial caecilian whose legless condition had evolved secondarily
107) Unlike eutherians, both monotremes and marsupials
A) lack nipples.
B) have some embryonic development outside the uterus.
C) lay eggs.
D) are found in Australia and Africa.
E) include only insectivores and herbivores.
108) Which clade does not include humans?
A) synapsids
B) lobe-fins
C) diapsids
D) craniates
E) osteichthyans
109) As hominins diverged from other primates, which of the following appeared first?
A) reduced jawbones
B) language
C) bipedal locomotion
D) the making of stone tools
E) an enlarged brain