Test Bank for Campbell Biology 13th Edition
by Urry Question and Answer (2026) | Newest
Update Verified Answers with Detailed
Rationales | A+ Verified
1) Which of the following is the correct sequence of events in the origin of life? I.
Formation of protocells II. Synthesis of organic monomers III. Synthesis of organic
polymers IV. Formation of DNA-based genetic systems | A) I, II, III, IV | B) I, III, II, IV | C)
II, III, I, IV | D) II, III, IV, I -✓✓C
2) Which of the following is a defining characteristic that all protocells had in common? |
A) the ability to synthesize enzymes | B) a surrounding membrane or membrane-like
structure | C) RNA genes | D) the ability to replicate RNA -✓✓B
3) The first genetic material on Earth was probably ________. | A) DNA produced by
reverse transcriptase from abiotically produced RNA | B) DNA molecules whose
information was transcribed to RNA and later translated in polypeptides | C) self-
replicating RNA molecules | D) oligopeptides located within protocells -✓✓C
4) In 2013, researchers constructed a vesicle with replicated RNA. Why was this
significant evidence for abiotic origin of life? | A) RNA molecules could pass on
information to their "daughters." | B) RNA molecules were not able to replicate. | C) RNA
would be used up by protocells. | D) RNA is a stable repository. -✓✓A
5) Which of the following statements suggests natural selection as a mechanism in the
evolution of ribozymes? | A) Single-stranded RNA has many shapes. | B) Replication of
RNA is flawless. | C) Some strands of RNA replicate less often. | D) Some strands of
RNA replicate more often and with more mutations. -✓✓C
6) How was early Earth from more than three billion years ago different from today's
Earth? Unlike Earth today, early Earth ________. | A) had an atmosphere rich in gases
released from volcanic eruptions | B) had an oxidizing atmosphere | C) experienced little
high-energy radiation from the sun | D) had an atmosphere with significant quantities of
ozone -✓✓A
7) Which hypothesis for the abiotic formation of organic molecules suggests that early
Earth's atmosphere was a neutral atmosphere? | A) The energy for this synthesis could
have come from lightning and UV radiation. | B) Some evidence suggests that the early
atmosphere was made up primarily of nitrogen and carbon dioxide. | C) Amino acids
were found near volcanic eruption sites. | D) Organic compounds were first produced in
deep-sea hydrothermal vents. -✓✓B
,8) Why are fossils considered to be an incomplete record of evolution? | A) The fossil
record shows changes in kinds of organisms that lived on earth. | B) The fossil record
shows that many animals are extinct. | C) The fossil record is biased for organisms that
had hard shells and skeletons. | D) Fossils document how new organisms come from
preexisting organisms. -✓✓C
9) What is the most accurate method used to measure the age of a fossil? | A)
radiometric dating | B) sequence fossils in rock strata | C) use uranium-238 | D) use
whole-life decay -✓✓A
10) Which of the following organisms would be most likely to form a fossil? | A) a rare
worm | B) a common worm | C) a rare squirrel | D) a common squirrel -✓✓D
11) Which of the following would be least likely to appear in the fossil record? | A)
burrowing species | B) marine-dwelling species | C) marsh-dwelling species | D) desert-
dwelling species -✓✓D
12) If the half-life of carbon-14 is about 5,730 years, then a fossil that has 1/16 of the
normal proportion of carbon-14 to carbon-12 should be about how many years old? | A)
2,800 | B) 11,200 | C) 16,800 | D) 22,900 -✓✓D
13) What is true of the fossil record of mammalian origins? | A) It shows that mammals
and birds evolved from the same kind of dinosaur. | B) It includes transitional forms with
progressively specialized teeth. | C) It indicates that mammals and dinosaurs did not
overlap in geologic time. | D) It includes a series that shows the gradual change of
scales into fur. -✓✓B
14) If a fossil is encased in a stratum of sedimentary rock without any strata of volcanic
rock (for example, lava or ash) nearby, then it should be ________. | A) easy to
determine the absolute age of the fossil, because the radioisotopes in the sediments will
not have been "reset" by the heat of the igneous rocks | B) easy to determine the
absolute age of the fossil, because the igneous rocks will not have physically obstructed
the deposition of sediment of a single age next to the fossil | C) difficult to determine the
absolute age of the fossil, because the "marker fossils" common to igneous rock will be
absent | D) difficult to determine the absolute age of the fossil, because radiometric
dating of sedimentary rock is less accurate than that of igneous rock -✓✓D
15) Use the following information to answer the question. A sediment core is removed
from the floor of an inland sea. The sea has been in existence, off and on, throughout
the entire time that terrestrial life has existed. Researchers wish to locate and study the
terrestrial organisms fossilized in this core. The core is illustrated as a vertical column,
with the top of the column representing the most recent strata and the bottom
representing the time when land was first colonized by life. To assign absolute dates to
fossils in this sediment core, it would be most helpful if ________. | A) you knew the
order in which the fossils occurred | B) the sediments had not been affected by
,underwater currents during their deposition | C) volcanic ash layers were regularly
interspersed between the sedimentary strata | D) fossils throughout the column were
equally spaced apart -✓✓C
16) Refer to the following information to answer the question. Fossils of Lystrosaurus, a
dicynodont therapsid, are most common in parts of modern-day South America, South
Africa, Madagascar, India, South Australia, and Antarctica. The animal apparently lived
in arid regions and was mostly herbivorous. It originated during the midPermian period,
survived the Permian extinction, and dwindled by the late Triassic, though there is
evidence of a relict population in Australia during the Cretaceous period. Some
dicynodonts had two large tusks, extending down from their upper jaws. The tusks were
not used for food gathering, and in some species were limited to males. Food was
gathered using an otherwise toothless beak. Judging from the fossil record in
sedimentary rocks, these pig-sized organisms were the most common mammal-like
reptiles of the Permian. What is thought to be the correct sequence of these events,
from earli -✓✓C
17) Which of the following showed their greatest diversity during the Mesozoic era but
were a small, less diverse group during the Paleozoic era? | A) gymnosperms | B) fungi
| C) flowering plants | D) mammals -✓✓A
18) Which listing of geological periods is in the correct order, from oldest to most
recent? | A) Cambrian, Devonian, Permian, Cretaceous | B) Devonian, Cambrian,
Permian, Cretaceous | C) Cambrian, Permian, Devonian, Cretaceous | D) Permian,
Cambrian, Cretaceous, Devonian -✓✓A
19) You are the lucky student of a wacky professor who develops a time machine. He
asks if you will test it with him. You get in, and there is an immediate glitch²the date
readout fails so that when you land, you are not sure what era you are in. Your
professor begins to panic, but you see something that tells you are in the Cenozoic era.
Which of the following could it be? | A) a rabbit eating a daisy | B) a water lily floating in
a pond | C) masses of green ferns with dragonflies hovering above them | D) a bee
pollinating a flower -✓✓A
20) You are the lucky student of a wacky professor who develops a time machine. He
asks if you will test it with him. You get in, and there is an immediate glitch²the date
readout fails so that when you land, you are not sure what era you are in. As your time
machine lands, you see an unusual landscape before you. As you open the door, you
realize you cannot breathe. You quickly shut the door, realizing you are in the
________. | A) Archaean eon | B) Cambrian period | C) Cenozoic era | D) Mesozoic era
-✓✓A
21) An early consequence of the release of oxygen gas by plant and bacterial
photosynthesis was to ________. | A) change the atmosphere from oxidizing to
reducing | B) make it easier to maintain reduced molecules | C) cause iron in ocean
, water and terrestrial rocks to rust (oxidize) | D) prevent the formation of an ozone layer -
✓✓C
22) What is true of the Cambrian explosion? | A) There are fossils of animals in
geological strata that are older than the Cambrian explosion. | B) Only the fossils of
microorganisms are found in geological strata older than the Cambrian explosion. | C)
The Cambrian explosion is evidence for the instantaneous creation of life on Earth. | D)
The Cambrian explosion marks the appearance of filter-feeding animals in the fossil
record. -✓✓A
23) Which of the following characteristics are expected in the first animals to have
colonized land? ÷ I) They were probably herbivores (ate photosynthesizers). II) Animals
had four appendages. III) Animals had the ability to resist dehydration. • IV) Animals had
lobe-finned fishes as ancestors. V) Invertebrates | A) III only | B) III and V | C) I, III and
V | D) I, II, III and IV -✓✓C
24) Use the following information to answer the question. A sediment core is removed
from the floor of an inland sea. The sea has been in existence, off and on, throughout
the entire time that terrestrial life has existed. Researchers wish to locate and study the
terrestrial organisms fossilized in this core. The core is illustrated as a vertical column,
with the top of the column representing the most recent strata and the bottom
representing the time when land was first colonized by life. If arrows indicate locations in
the column where fossils of a particular type (see key) first appear, then which core in
the figure above has the most accurate arrangement of fossils? | A) core A | B) core B |
C) core C | D) core D -✓✓A
25) Which factor most likely caused animals and plants in India to differ greatly from
species in nearby southeast Asia? | A) The climates of the two regions are similar. | B)
India is in the process of separating from the rest of Asia. | C) Life in India was wiped
out by ancient volcanic eruptions. | D) India was a separate continent until 45 million
years ago. -✓✓D
26) What concept explains the evolution of complex eyes? | A) Complex eyes evolved
through a series of steps that benefited the eyes. | B) Mollusc eyes evolved from a
different ancestor than vertebrate eyes. | C) Through evolutionary history, eyes lose
function of vision. | D) Mollusc eye's evolution was dependent on vertebrate eye
evolution. -✓✓A
27) How does continental drift explain the uniqueness of Australian fauna? | A)
Marsupials fill the ecological niche as eutherians on other continents. | B) Fossil
evidence suggests that marsupials originated in Asia and reached Australia via South
America. | C) The subsequent separation of the southern continents formed an island of
marsupials. | D) In Australia, marsupials diversified, and eutherians became extinct. -
✓✓C
by Urry Question and Answer (2026) | Newest
Update Verified Answers with Detailed
Rationales | A+ Verified
1) Which of the following is the correct sequence of events in the origin of life? I.
Formation of protocells II. Synthesis of organic monomers III. Synthesis of organic
polymers IV. Formation of DNA-based genetic systems | A) I, II, III, IV | B) I, III, II, IV | C)
II, III, I, IV | D) II, III, IV, I -✓✓C
2) Which of the following is a defining characteristic that all protocells had in common? |
A) the ability to synthesize enzymes | B) a surrounding membrane or membrane-like
structure | C) RNA genes | D) the ability to replicate RNA -✓✓B
3) The first genetic material on Earth was probably ________. | A) DNA produced by
reverse transcriptase from abiotically produced RNA | B) DNA molecules whose
information was transcribed to RNA and later translated in polypeptides | C) self-
replicating RNA molecules | D) oligopeptides located within protocells -✓✓C
4) In 2013, researchers constructed a vesicle with replicated RNA. Why was this
significant evidence for abiotic origin of life? | A) RNA molecules could pass on
information to their "daughters." | B) RNA molecules were not able to replicate. | C) RNA
would be used up by protocells. | D) RNA is a stable repository. -✓✓A
5) Which of the following statements suggests natural selection as a mechanism in the
evolution of ribozymes? | A) Single-stranded RNA has many shapes. | B) Replication of
RNA is flawless. | C) Some strands of RNA replicate less often. | D) Some strands of
RNA replicate more often and with more mutations. -✓✓C
6) How was early Earth from more than three billion years ago different from today's
Earth? Unlike Earth today, early Earth ________. | A) had an atmosphere rich in gases
released from volcanic eruptions | B) had an oxidizing atmosphere | C) experienced little
high-energy radiation from the sun | D) had an atmosphere with significant quantities of
ozone -✓✓A
7) Which hypothesis for the abiotic formation of organic molecules suggests that early
Earth's atmosphere was a neutral atmosphere? | A) The energy for this synthesis could
have come from lightning and UV radiation. | B) Some evidence suggests that the early
atmosphere was made up primarily of nitrogen and carbon dioxide. | C) Amino acids
were found near volcanic eruption sites. | D) Organic compounds were first produced in
deep-sea hydrothermal vents. -✓✓B
,8) Why are fossils considered to be an incomplete record of evolution? | A) The fossil
record shows changes in kinds of organisms that lived on earth. | B) The fossil record
shows that many animals are extinct. | C) The fossil record is biased for organisms that
had hard shells and skeletons. | D) Fossils document how new organisms come from
preexisting organisms. -✓✓C
9) What is the most accurate method used to measure the age of a fossil? | A)
radiometric dating | B) sequence fossils in rock strata | C) use uranium-238 | D) use
whole-life decay -✓✓A
10) Which of the following organisms would be most likely to form a fossil? | A) a rare
worm | B) a common worm | C) a rare squirrel | D) a common squirrel -✓✓D
11) Which of the following would be least likely to appear in the fossil record? | A)
burrowing species | B) marine-dwelling species | C) marsh-dwelling species | D) desert-
dwelling species -✓✓D
12) If the half-life of carbon-14 is about 5,730 years, then a fossil that has 1/16 of the
normal proportion of carbon-14 to carbon-12 should be about how many years old? | A)
2,800 | B) 11,200 | C) 16,800 | D) 22,900 -✓✓D
13) What is true of the fossil record of mammalian origins? | A) It shows that mammals
and birds evolved from the same kind of dinosaur. | B) It includes transitional forms with
progressively specialized teeth. | C) It indicates that mammals and dinosaurs did not
overlap in geologic time. | D) It includes a series that shows the gradual change of
scales into fur. -✓✓B
14) If a fossil is encased in a stratum of sedimentary rock without any strata of volcanic
rock (for example, lava or ash) nearby, then it should be ________. | A) easy to
determine the absolute age of the fossil, because the radioisotopes in the sediments will
not have been "reset" by the heat of the igneous rocks | B) easy to determine the
absolute age of the fossil, because the igneous rocks will not have physically obstructed
the deposition of sediment of a single age next to the fossil | C) difficult to determine the
absolute age of the fossil, because the "marker fossils" common to igneous rock will be
absent | D) difficult to determine the absolute age of the fossil, because radiometric
dating of sedimentary rock is less accurate than that of igneous rock -✓✓D
15) Use the following information to answer the question. A sediment core is removed
from the floor of an inland sea. The sea has been in existence, off and on, throughout
the entire time that terrestrial life has existed. Researchers wish to locate and study the
terrestrial organisms fossilized in this core. The core is illustrated as a vertical column,
with the top of the column representing the most recent strata and the bottom
representing the time when land was first colonized by life. To assign absolute dates to
fossils in this sediment core, it would be most helpful if ________. | A) you knew the
order in which the fossils occurred | B) the sediments had not been affected by
,underwater currents during their deposition | C) volcanic ash layers were regularly
interspersed between the sedimentary strata | D) fossils throughout the column were
equally spaced apart -✓✓C
16) Refer to the following information to answer the question. Fossils of Lystrosaurus, a
dicynodont therapsid, are most common in parts of modern-day South America, South
Africa, Madagascar, India, South Australia, and Antarctica. The animal apparently lived
in arid regions and was mostly herbivorous. It originated during the midPermian period,
survived the Permian extinction, and dwindled by the late Triassic, though there is
evidence of a relict population in Australia during the Cretaceous period. Some
dicynodonts had two large tusks, extending down from their upper jaws. The tusks were
not used for food gathering, and in some species were limited to males. Food was
gathered using an otherwise toothless beak. Judging from the fossil record in
sedimentary rocks, these pig-sized organisms were the most common mammal-like
reptiles of the Permian. What is thought to be the correct sequence of these events,
from earli -✓✓C
17) Which of the following showed their greatest diversity during the Mesozoic era but
were a small, less diverse group during the Paleozoic era? | A) gymnosperms | B) fungi
| C) flowering plants | D) mammals -✓✓A
18) Which listing of geological periods is in the correct order, from oldest to most
recent? | A) Cambrian, Devonian, Permian, Cretaceous | B) Devonian, Cambrian,
Permian, Cretaceous | C) Cambrian, Permian, Devonian, Cretaceous | D) Permian,
Cambrian, Cretaceous, Devonian -✓✓A
19) You are the lucky student of a wacky professor who develops a time machine. He
asks if you will test it with him. You get in, and there is an immediate glitch²the date
readout fails so that when you land, you are not sure what era you are in. Your
professor begins to panic, but you see something that tells you are in the Cenozoic era.
Which of the following could it be? | A) a rabbit eating a daisy | B) a water lily floating in
a pond | C) masses of green ferns with dragonflies hovering above them | D) a bee
pollinating a flower -✓✓A
20) You are the lucky student of a wacky professor who develops a time machine. He
asks if you will test it with him. You get in, and there is an immediate glitch²the date
readout fails so that when you land, you are not sure what era you are in. As your time
machine lands, you see an unusual landscape before you. As you open the door, you
realize you cannot breathe. You quickly shut the door, realizing you are in the
________. | A) Archaean eon | B) Cambrian period | C) Cenozoic era | D) Mesozoic era
-✓✓A
21) An early consequence of the release of oxygen gas by plant and bacterial
photosynthesis was to ________. | A) change the atmosphere from oxidizing to
reducing | B) make it easier to maintain reduced molecules | C) cause iron in ocean
, water and terrestrial rocks to rust (oxidize) | D) prevent the formation of an ozone layer -
✓✓C
22) What is true of the Cambrian explosion? | A) There are fossils of animals in
geological strata that are older than the Cambrian explosion. | B) Only the fossils of
microorganisms are found in geological strata older than the Cambrian explosion. | C)
The Cambrian explosion is evidence for the instantaneous creation of life on Earth. | D)
The Cambrian explosion marks the appearance of filter-feeding animals in the fossil
record. -✓✓A
23) Which of the following characteristics are expected in the first animals to have
colonized land? ÷ I) They were probably herbivores (ate photosynthesizers). II) Animals
had four appendages. III) Animals had the ability to resist dehydration. • IV) Animals had
lobe-finned fishes as ancestors. V) Invertebrates | A) III only | B) III and V | C) I, III and
V | D) I, II, III and IV -✓✓C
24) Use the following information to answer the question. A sediment core is removed
from the floor of an inland sea. The sea has been in existence, off and on, throughout
the entire time that terrestrial life has existed. Researchers wish to locate and study the
terrestrial organisms fossilized in this core. The core is illustrated as a vertical column,
with the top of the column representing the most recent strata and the bottom
representing the time when land was first colonized by life. If arrows indicate locations in
the column where fossils of a particular type (see key) first appear, then which core in
the figure above has the most accurate arrangement of fossils? | A) core A | B) core B |
C) core C | D) core D -✓✓A
25) Which factor most likely caused animals and plants in India to differ greatly from
species in nearby southeast Asia? | A) The climates of the two regions are similar. | B)
India is in the process of separating from the rest of Asia. | C) Life in India was wiped
out by ancient volcanic eruptions. | D) India was a separate continent until 45 million
years ago. -✓✓D
26) What concept explains the evolution of complex eyes? | A) Complex eyes evolved
through a series of steps that benefited the eyes. | B) Mollusc eyes evolved from a
different ancestor than vertebrate eyes. | C) Through evolutionary history, eyes lose
function of vision. | D) Mollusc eye's evolution was dependent on vertebrate eye
evolution. -✓✓A
27) How does continental drift explain the uniqueness of Australian fauna? | A)
Marsupials fill the ecological niche as eutherians on other continents. | B) Fossil
evidence suggests that marsupials originated in Asia and reached Australia via South
America. | C) The subsequent separation of the southern continents formed an island of
marsupials. | D) In Australia, marsupials diversified, and eutherians became extinct. -
✓✓C
