Czako Test 2 (study for final part 2)
Which of the following is found in eukaryotic cells but not in prokaryotic cells?
a) plasma membrane
b) membrane-enclosed organelles
d) cell wall
Which of the following can promote allopatric speciation but not sympatric speciation?
a) sexual selection
c) geographic isolation
d) natural selection
iller and Urey's experiments that attempted to recreate conditions on early Earth were significant because _____.
a) they showed that organic molecules such as amino acids could be produced from inorganic molecules
b) they showed how polymers could form spontaneously on a clay substrate
c) they showed how radiometric dating could be used to give the absolute ages of rocks and fossils
d) proved the endosymbiotic theory
e) they produced the first protocells
Why do some scientists believe that RNA, rather than DNA, was the first genetic material?
a) All the proto-cells on early Earth contained RNA.
b) RNA can replicate more accurately than DNA.
c) RNA has both information storage and catalytic properties.
d) RNA could have evolved into DNA.
e) RNA contains uracil in place of thymine
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) II, III, I, IV
b) II, III, IV, I
c) I, II, III, IV
d) I, III, II, IV
Which of the following is a defining characteristic that all protocells had in common?
a) the ability to replicate RNA
b) a surrounding membrane or membrane-like structure
c) RNA genes
d) the ability to synthesize enzymes
The first genetic material on Earth was probably ________.
a) DNA produced by reverse transcriptase from abiotically produced RNA
b) self-replicating RNA molecules
c) oligopeptides located within protocells
d) DNA molecules whose information was transcribed to RNA and later translated in polypeptides
Which of the following statements suggests natural selection as a mechanism in the evolution of ribozymes?
a) Single-stranded RNA has many shapes.
b) Some strands of RNA replicate less often.
c) Some strands of RNA replicate more often and with more mutations.
d) Replication of RNA is flawless.
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.
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) experienced little high-energy radiation from the sun
c) had an atmosphere with significant quantities of ozone
d) had an oxidizing atmosphereSubmit
Which hypothesis for the abiotic formation of organic molecules suggests that early Earth's atmosphere was a neutral atmosphere?
a) Some evidence suggests that the early atmosphere was made up primarily of nitrogen and carbon dioxide.
b) Organic compounds were first produced in deep-sea hydrothermal vents.
c) Amino acids were found near volcanic eruption sites.
d) The energy for this synthesis could have come from lightning and UV radiation.
One hypothesis that has been proposed regarding the origin of life suggests that life evolved from an "RNA world" to todays "DNA world." Considering the properties of RNA and DNA molecules, which questions would direct an investigation of the most insightful test(s) of this hypothesis?
a) Could RNA have provided a template for DNA assembly, thereby enabling a more stable molecule that is replicated more accurately?
b) Is it likely that simple, yet stable RNA molecules served as a primitive precursor to a less stable DNA molecule that was more capable of storing more information?
c) Since ribozymes could freely enter and leave the vesicles, could these molecules have brought external DNA into the cell as a less stable, but more reliable storage molecule of double-stranded DNA?
d) Is it likely that RNA molecules functioned as ribozymes to synthesize DNA from amino acids, and that this role was reversed when DNA became the information source?
The oldest fossils usually _____.
a) contain more radioactive isotopes than younger fossils
b) are found in the deepest strata
c) are found in sediments formed during the Cenozoic era
d) are found above younger fossils
e) have the longest half-lives
Radiometric dating _____.
a) can be used to directly date fossils in sedimentary rock
b) allows us to determine an absolute, errorless date
c) only works on rocks younger than 75,000 years
d) allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata
e) relies on the fact that the daughter isotope decays to the parent isotope at a constant rate
Why are fossils considered to be an incomplete record of evolution?
a) The fossil record shows that many animals are extinct.
b) The fossil record is biased for organisms that had hard shells and skeletons.
c) Fossils document how new organisms come from preexisting organisms.
d) The fossil record shows changes in kinds of organisms that lived on earth.
What is the most accurate method used to measure the age of a fossil?
a) radiometric dating
b) use uranium-238
c) sequence fossils in rock strata
d) use whole-life decay
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?
What is true of the fossil record of mammalian origins?
a) It indicates that mammals and dinosaurs did not overlap in geologic time.
b) It includes a series that shows the gradual change of scales into fur.
c) It includes transitional forms with progressively specialized teeth.
d) It shows that mammals and birds evolved from the same kind of dinosaur.
In the origin of the eukaryotes, endosymbiosis
a) most likely began with the endosymbiont entering the host cell through the endomembrane system.
b) is thought to explain the origin of the nucleus.
c) describes the engulfing of a photosynthetic bacterium that ultimately gave rise to mitochondria.
d) most likely began with a heterotrophic endosymbiont entering the cell as undigested prey or as an internal parasite.
During the origin of the eukaryotic cell, it is thought that engulfed bacteria
a) always had a mutually beneficial relationship with their hosts.
b) did not initially have a mutually beneficial relationship with their hosts, but later evolved one.
c) were always harmful to their hosts.
d) had a mutually beneficial relationship with their hosts initially, but later evolved to become harmful to their hosts.
The atmosphere of early Earth probably contained no O2 until the emergence of organisms that _____.
a) were chemoautotrophic
b) used water as an electron source for photosynthesis
c) were oxygen respiring
d) used hydrogen sulfide as an energy source
e) had chloroplasts
The earliest organisms were most likely _____.
e) plants and fungi
What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth?
1. origin of mitochondria
2. origin of multicellular eukaryotes
3. origin of chloroplasts
4. origin of cyanobacteria
5. origin of fungal-plant symbioses
a) 4, 1, 2, 3, 5
b) 4, 3, 1, 5, 2
c) 4, 1, 3, 2, 5
d) 4, 3, 2, 1, 5
An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to _____.
a) make it easier to maintain reduced molecules
b) cause iron in ocean water and terrestrial rocks to rust (oxidize)
c) change the atmosphere from oxidizing to reducing
d) prevent the formation of an ozone layer
What is true of the Cambrian explosion?
a) There are fossils of animals in geological strata that are older than the Cambrian explosion.
b) The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record.
c) Only the fossils of microorganisms are found in geological strata older than the Cambrian explosion.
d) The Cambrian explosion is evidence for the instantaneous creation of life on Earth.
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.
a) I, III and V
b) I, II, III and IV
c) III and V
d) III only
Endosymbiosis is an evolutionary theory that explains the origin of eukaryotes and suggests a specific order in which this might have occurred. Ancestral cells engulfed and then began to use the metabolic processes of the smaller cells. Based on shared-core processes and features, which statement most accurately describes the order, the theory, and the evolutionary implications for all organisms within domain Eukarya?
a) As carbon dioxide levels were increasing over time, natural selection would have favored organisms that acquired a photosynthetic prokaryote to convert carbon dioxide into sugars. These would have likely been the first eukaryotic cells. These ancestral cells engulfed mitochondria-like prokaryotes, which would have provided an even greater advantage for cells in this environment.
b) All ancestral eukaryotes would have most likely consumed a nucleus-like prokaryote that eventually became the eukaryotic nucleus. These new eukaryotic cells would have had an advantage over prokaryotic cells by acquiring a nuclear command center for regulating cellular activities.
c) As Earth was becoming more aerobic, mitochondria would have provided an advantage to host cells by converting "toxic" oxygen into energy for heterotrophic cells. Since mitochondria are found in all eukaryotes, these combinations likely evolved first. Photosynthetic eukaryotes probably acquired an autotrophic prokaryote, which developed an advantageous symbiotic relationship with the host cell.
d) Ancestral heterotrophic eukaryotes most likely engulfed both a heterotrophic and an autotrophic prokaryote, whereas ancestral photosynthetic eukaryotes probably provided the host cell for the first mitochondria. Over time, natural selection favored these relationships, and these cells became ancestors of all eukaryotes.
Which of the following statements about adaptive radiation is correct?
a) Adaptive radiation occurs in species that live in one habitat.
b) Adaptive radiation occurs in the presence of competitors.
c) Adaptive radiation occurs within a single lineage.
d) Adaptive radiation occurs very slowly over time.
Which organisms are not examples of an adaptive radiation?
a) Horses and deer in the post-dinosaur age
b) Anolis lizards of the Caribbean
c) Mammals and reptiles in the post-dinosaur age
d) Honeycreeper songbirds of the Hawaiian islands
True or false? Convergent evolution is said to have occurred if the mouse species on two islands with similar habitats are found to have similar characteristics even though they originated from different species that did not have these characteristics.
Which Anolis lizard ecomorph has long legs?
Which of the following statements about the evolution of Anolis lizards in the Caribbean islands is true?
a) The genetic relatedness of ecomorphs was determined by comparing their nuclear DNA sequences.
b) The phylogeny of ecomorphs on a given island reveals that adaptive radiation has taken place.
c) A crown ecomorph living on one island is always the same species as a crown ecomorph living on a neighboring island.
d) Twig ecomorphs can jump very well.
What was the main selective pressure behind the evolution of different Anolis lizard species in the Caribbean?
b) Specific ecological niches
True or false? The evolution of different ecomorphs on the Caribbean islands is an example of stabilizing selection.
How does continental drift affect living organisms?
a) It causes climate change, which puts selective pressure on organisms.
b) It causes changes in habitats, such as when large amounts of shallow marine habitat were lost in the formation of Pangaea.
c) It may cause an increase or decrease in competition among different species.
d) It happens so slowly that it does not affect living organisms.
e)All but one of these are correct.
Which factor most likely caused animals and plants in India to differ greatly from species in nearby southeast Asia?
a) India was a separate continent until 45 million years ago.
b) India is in the process of separating from the rest of Asia.
c) The climates of the two regions are similar.
d) Life in India was wiped out by ancient volcanic eruptions.
How does continental drift explain the uniqueness of Australian fauna?
a) The subsequent separation of the southern continents formed an island of marsupials.
b) In Australia, marsupials diversified, and eutherians became extinct.
c) Marsupials fill the ecological niche as eutherians on other continents.
d) Fossil evidence suggests that marsupials originated in Asia and
reached Australia via
Hox genes are thought to play an important role in the development of different morphologies because _____.
a) they affect the timing of reproductive development in the organism
b) they paved the way for the development of multicellular organisms
c) they provide positional information in the embryo
d) they affect the order of genes on certain chromosomes
e) they affect the timing of development in the embryo
A female fly, full of fertilized eggs, is swept by high winds to an
island far out to sea. She is the first fly to arrive on this island
and the only fly to arrive in this way. Thousands of years later, her
numerous offspring occupy the island, but none of them resembles her.
There are, instead, several species, each of which eats only a certain
type of food. None of the species can fly and their balancing organs
(halteres) are now used in courtship displays. The male members of
each species bear modified halteres that are unique in appearance to
their species. Females bear vestigial halteres. The ranges of all of
the daughter species overlap.
In each fly species, the entire body segment that gave rise to the original flight wings is missing. The mutation(s) that led to the flightless condition could have _____.altered the expression of a Hox geneoriginated in another speciesduplicated all of the Hox genes in these flies' genomesresulted in paedomorphosis