Mastering Biology 6

What is the most important factor that holds a gene pool of a species together and prevents speciation? A-prezygotic barriers B-sexual selection C-hybridization D-gene flow E-behavioral isolation

Two animals are considered members of different species if they _____. A-are members of different populations B-are geographically isolated C-live in different habitats D-look different E-cannot mate and produce viable, fertile offspring

Which of these is an example of temporal isolation? A-One is a type of primate, the other is a type of marsupial. B-One species performs a specific courtship dance. the other species does not. C-One species is found only in New York, the other only in London. D-The average weight of the individuals in one species is 45 kg; in the other species the average is 290 kg. E-One species is nocturnal, and the other species is not.

Which of the following is the first step in allopatric speciation? A-hybridization B-polyploidy C-formation of a reproductive barrier D-genetic drift E-geographic isolation

Two populations of birds with somewhat different coloration live on opposite sides of a peninsula. The habitat between the populations is not suitable for these birds. When birds from the two populations are brought together, they produce young whose appearance is intermediate between the two parents. These offspring will breed with each other or with birds from either parent population, and all offspring of these pairings appear intermediate to various degrees. What keeps the two populations separate? A-habitat isolation B-temporal reproductive isolation C-behavioral reproductive isolation D-lack of hybrid viability

Three populations of crickets look very similar, but the males have courtship songs that sound different. What function would this difference in song likely serve if the populations came in contact? A-a gametic reproductive isolating mechanism B-a temporal reproductive isolating mechanism C-a behavioral reproductive isolating mechanism D-a postzygotic isolating mechanism

The peppered moth provides a well-known example of natural selection. The light-colored form of the moth was predominant in England before the Industrial Revolution. In the mid-nineteenth century, a dark-colored form appeared. The difference is produced by a dominant allele of one gene. By about 1900, approximately 90% of the moths around industrial areas were dark colored, whereas light-colored moths were still abundant elsewhere. Apparently, birds could readily find the light moths against the soot-darkened background in industrial areas and, therefore, were eating more light moths. Recently, use of cleaner fuels has greatly reduced soot in the landscape, and the dark-colored moths have been disappearing. Should the two forms of moths be considered separate species? A-Yes, because they are reproductively isolated based on habitat. B-Yes, because natural selection has affected the frequency of the two different forms. C-Yes, because they have completely different coloration. D-No.

The common edible frog of Europe is a hybrid between two species, Rana lessonae and Rana ridibunda. The hybrids were first described in 1758 and have a wide distribution, from France across central Europe to Russia. Both male and female hybrids exist, but when they mate among themselves, they are rarely successful in producing offspring. What can you infer from this information? A-Postzygotic isolation exists between the two frog species. B-The hybrids form a separate species under the biological species concept. C-These two species are likely in the process of fusing back into one species. D-Prezygotic isolation exists between the two frog species.

Macroevolution is _____. A-defined as a change in allele or gene frequency over the course of many generations B-defined as the evolution of microscopic organisms into organisms that can be seen with the naked eye C-evolution new species D-change in allele frequencies over time

Which of the various species concepts distinguishes two species based on the degree of genetic exchange between their gene pools? A-phylogenetic B-morphological C-ecological D-biological

You are confronted with a box of preserved grasshoppers of various species that are new to science and have not been described. Your assignment is to separate them into species. There is no accompanying information as to where or when they were collected. Which species concept will you have to use? A-ecological B-phylogenetic C-morphological D-biological

Rank the following in order from most general to most specific: 1. gametic isolation 2. reproductive isolating mechanism 3. sperm-egg incompatibility in sea urchins 4. prezygotic isolating mechanism A-2, 4, 1, 3 B-4, 1, 2, 3 C-4, 2, 1, 3 D-2, 3, 1, 4

Two species of frogs belonging to the same genus occasionally mate, but the embryos stop developing after a day and then die. These two frog species separate by _____. A-reduced hybrid fertility B-gametic isolation C-reduced hybrid viability D-hybrid breakdown

The production of sterile mules by interbreeding between female horses (mares) and male donkeys (jacks) is an example of _____. A-reduced hybrid fertility B-mechanical isolation C-reduced hybrid viability D-hybrid breakdown

Dogs (Canis lupus familiaris) and gray wolves (Canis lupus) can interbreed to produce viable, fertile offspring. These species shared a common ancestor recently (in geologic time) and have a high degree of genetic similarity, although their anatomies vary widely. Judging from this evidence, which two species concepts are most likely to place dogs and wolves together into a single species? A-biological and phylogenetic B-ecological and phylogenetic C-biological and morphological D-ecological and morphological

What is genetic drift? A-A change in allele frequencies caused by random events B-The physical splitting of a habitat C-The production of an evolutionarily independent group of organisms D-The motion of continental plates over time

Why are the large finches now living on the Galápagos Islands different from the original source population from a nearby island? A-Natural selection favored individuals that were more fit in the new environment. B-All three answers are correct. C-Genetic drift occurred in the two populations. D-The separation of habitats reduced gene flow between the populations.

True or false? The last ice age produced many different species mainly because populations dispersed and colonized new habitats. A-True B-False

Which of the following statements about reinforcement is true? A-Reinforcement increases the number of intermediate phenotypes. B-Reinforcement decreases the morphological difference between two incipient species. C-Reinforcement is also called dispersive selection. D-Reinforcement is a type of natural selection.

A subset of a population of birds leaves its habitat on the mainland and colonizes a nearby island. The birds, after a period of time, become reproductively isolated. The island sinks and the population of birds that lived on the island returns to its original habitat. Which of the following statements about these bird populations is true? A-The populations will be able to interbreed even though they are different species. B-The birds were separated by a vicariance event. C-The populations were sympatric while they diverged. D-The populations will not be able to interbreed because they are different species.

A population of birds colonizes an area in which the insects upon which they feed live inside trees. Which of the following events accounts for an observed increase in average beak size in the bird population over time? A-Increased fitness of large-beaked birds, leading to natural selection B-Decreased fitness of small-beaked birds, creating a new species C-Decreased fitness of the insects, allowing the birds to catch them more easily D-Increased fitness of the large-beaked birds, creating a new species

True or false? A flood that separates a population of frogs onto opposite sides of a lake is an example of a vicariance event that may result in allopatric speciation. A-True B-False

Which term is used to describe populations that live close enough to interbreed? A-Allopatry B-Speciation C-Polyploidy D-Sympatry

What prevents speciation from occurring in sympatric populations? A-Geographical isolation B-Genetic drift C-Natural selection D-Gene flow

True or false? A mating between a tetraploid individual and a diploid individual produces biologically fit offspring. A-True B-False

Which of the following statements about autopolyploid individuals is true? A-They can never produce viable offspring. B-They can always produce fertile offspring. C-They contain more than two haploid sets of chromosomes. D-They result from matings between individuals of different species.

What would be the ploidy of the viable gametes produced by a tetraploid individual if nondisjunction of all chromosomes occurred in meiosis I? A-Tetraploid B-Triploid C-Haploid D-Diploid

How can an allopolyploid plant become a biologically fit new species? A-Nondisjunction event during meiosis B-Synapsis of homologous chromosomes C-Nondisjunction event during mitosis D-Allopolyploid plants cannot become biologically fit new species; they are always sterile.

How many chromosomes would be found in an allopolyploid plant if its parents had diploid numbers of 2 and 10, respectively? A-Haploid number of 12 B-Diploid number of 6 C-Diploid number of 12 D-Haploid number of 6

Sympatric speciation is _____. A-the emergence of many species from a single ancestor B-especially important in the evolution of island species C-initiated by the appearance of a geographic barrier D-the process by which most animal species have evolved E-the appearance of a new species in the same area as the parent population

Which of the following has been shown to cause speciation most rapidly? A-differential resource exploitation B-sexual selection C-hybridization D-autopolyploidy E-punctuated equilibrium

Which of the following describes the most likely order of events in allopatric speciation? A-genetic isolation, genetic drift, divergence B-divergence, genetic drift, genetic isolation C-genetic isolation, divergence, genetic drift D-genetic drift, genetic isolation, divergence

House finches were found only in western North America until 1939, when a few individuals were released in New York City. These individuals established a breeding population and gradually expanded their range. The western population also expanded its range somewhat eastward, and the two populations have recently come in contact. If the two forms were unable to interbreed when their expanding ranges met, it would be an example of _____. A-reinforcement B-sympatric speciation C-allopatric speciation D-prezygotic isolation

Most causes of speciation are relatively slow, in that they may take many generations to see changes, with the exception of _____. A-reinforcement B-polyploidy C-natural selection D-colonization

Two researchers experimentally formed tetraploid frogs by fertilizing diploid eggs from Rana porosa brevipoda with diploid sperm from Rana nigromaculata. When they mated these tetraploid frogs with each other, most of the offspring that survived to maturity were tetraploid, with chromosome sets of both diploid parent species. Based on these results, if this type of tetraploid formed in the wild, what would be the result? (Y. Kondo and A. Kashiwagi. 2004. Experimentally induced autotetraploidy and allotetraploidy in two Japanese pond frogs. Journal of Herpetology 38(3):381-92.) A-The tetraploids would be reproductively isolated from both parent species. B-The two parent species would recognize each other as mates. C-The two parent species would interbreed and fuse into one species. D-The tetraploids would be selected against.

A researcher notices that in a certain moth species, some females prefer to feed and lay eggs on domesticated solanaceous plants like potatoes and tomatoes. Other females prefer to feed and lay eggs on wild solanaceous plants like Datura. Both male and female moths primarily use scent to find these plants from afar. Females tend to mate where they feed, and the researcher finds a genetic basis for scent preference in these moths. Based on the above information, what might be occurring in this moth species? A-polyploidization B-postzygotic isolation C-divergence in sympatry D-divergence due to habitat fragmentation

Two species of tree frogs that live sympatrically in the northeastern United States differ in ploidy: Hyla chrysoscelis is diploid, and Hyla versicolor is tetraploid. The frogs are identical in appearance, but their mating calls, which females use to find mates, differ. Which difference most likely evolved first? A-difference in mating calls B-polyploidy C-Polyploidy and different mating calls must have evolved at the same time.

Plant species A has a diploid number of 12. Plant species B has a diploid number of 16. A new species, C, arises as an allopolyploid from A and B. The diploid number for species C would probably be _____. A-56 B-16 C-14 D-28

A small number of birds arrive on an island from a neighboring larger island. This small population begins to adapt to the new food plants available on the island, and their beaks begin to change. About twice a year, one or two more birds from the neighboring island arrive. These new arrivals _____. A-speed up the process of speciation B-tend to promote adaptation to the new food plants C-represent a colonizing event D-tend to retard adaptation to the new food plants

According to the _____ model, evolution occurs in spurts; species evolve relatively rapidly then remain unchanged for long periods. A-gradualist B-geographic isolation C-nondisjunction D-punctuated equilibrium E-adaptive radiation

According to the concept of punctuated equilibrium, the "sudden" appearance of a new species in the fossil record means that _____. A-the species is now extinct B-speciation occurred in one generation C-speciation occurred rapidly in geologic time D-the species will consequently have a relatively short existence, compared with other species

According to the concept of punctuated equilibrium, _____. A-a new species accumulates most of its unique features as it comes into existence B-evolution of new species features long periods during which changes are occurring, interspersed with short periods of equilibrium, or stasis C-given enough time, most existing species will gradually give rise to new species D-natural selection is unimportant as a mechanism of evolution

Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting other males and making stylized movements that attract females. What type of reproductive isolation does this represent? A-behavioral isolation B-postzygotic barriers C-gametic isolation D-temporal isolation E-habitat isolation

Earth probably formed _____ years ago, and the first life evolved as early as _____ years ago. A-4.5 billion years ago ... 3.9 billion years ago B-10 billion years ago ... 4.5 billion years ago C-6,000 years ago ... 6,000 years ago D-3.9 million years ago ... 2.0 billion years ago E-Humans observed neither event, so there is no way to tell.

Radiometric dating _____. A-allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata B-allows us to determine an absolute, errorless date C-relies on the fact that the daughter isotope decays to the parent isotope at a constant rate D-can be used to directly date fossils in sedimentary rock E-only works on rocks younger than 75,000 years

Which of the following organisms would be most likely to fossilize? A-a rare squirrel B-a common squirrel C-a rare worm D-a common worm

Which of the following would be LEAST likely in the fossil record? A-marine-dwelling species B-burrowing species C-desert-dwelling species D-marsh-dwelling species

If the half-life of carbon-14 is about 5730 years, then a fossil that has one-sixteenth the normal proportion of carbon-14 to carbon-12 should be about how many years old? A-22,900 B-16,800 C-2800 D-11,200

Reptiles first appeared during the _____ era. A-Paleozoic B-Triassic C-Mesozoic D-Cenozoic E-Jurassic

We are living during the _____era. A-Neogene B-Cenozoic C-Paleozoic D-Paleogene E-Mesozoic

Dinosaurs went extinct during the _____. A-Devonian B-Precambrian C-Mesozoic D-Cenozoic E-Carboniferous

_____ were the dominant vertebrate life form during the Paleozoic era. A-Amphibians B-Reptiles C-Sponges D-Dinosaurs E-Mammals

Life arose during the _____. A-Precambrian B-Cenozoic C-Triassic D-Paleozoic E-Mesozoic

Flowering plants first appeared during the _____. A-Devonian B-Precambrian C-Mesozoic D-Cenozoic E-Carboniferous

The Mesozoic era began approximately _____ million years ago. A-4,600 B-570 C-251 D-65 E-25

The Precambrian time began at least _____ million years ago. A-4,600 B-570 C-245 D-65 E-25

Seed plants first appeared during the _____. A-Paleozoic B-Triassic C-Mesozoic D-Cenozoic E-Jurassic

The first prokaryotic cells appeared during the _____. A-Jurassic B-Cretaceous C-Paleozoic D-Triassic E-Precambrian

Animals first appeared during the _____. A-Mesozoic B-Paleozoic C-Precambrian D-Silurian E-Cenozoic

The Cenozoic era began approximately _____ million years ago. A-4,600 B-570 C-245 D-65 E-25

_____ were the dominant vertebrate life form during the Mesozoic era. A-Dinosaurs B-Mammals C-Fish D-Birds E-Amphibians

Most modern animal phyla evolved during the _____ era. A-Paleozoic B-Cenozoic C-Mesozoic D-Precambrian

Bony fish first evolved during the _____ . A-Mesozoic B-Paleozoic C-Cenozoic D-Precambrian E-Cretaceous

The earliest organisms were most likely _____. A-multicellular B-prokaryotic C-eukaryotic D-proto-cells E-plants and fungi

The atmosphere of early Earth probably contained no O2 until the emergence of organisms that _____. A-used hydrogen sulfide as an energy source B-were chemoautotrophic C-used water as an electron source for photosynthesis D-had chloroplasts E-were oxygen respiring

Which of the following was derived from an ancestral cyanobacterium? A-chloroplast B-mitochondrion C-flagella D-mitosome

An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to _____. A-cause iron in ocean water and terrestrial rocks to rust (oxidize) B-change the atmosphere from oxidizing to reducing C-prevent the formation of an ozone layer D-make it easier to maintain reduced molecules

What is true of the Cambrian explosion? A-The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record. 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-There are fossils of animals in geological strata that are older than the Cambrian explosion.

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-India was a separate continent until forty-five million years ago. D-Life in India was wiped out by ancient volcanic eruptions.

The following question refer to the description below. All animals with eyes or eyespots that have been studied so far share a gene in common. When mutated, the gene Pax-6 causes lack of eyes in fruit flies, tiny eyes in mice, and missing irises (and other eye parts) in humans. The sequence of Pax-6 in humans and mice is identical. There are so few sequence differences with fruit fly Pax-6 that the human/mouse version can cause eye formation in eyeless fruit flies, even though vertebrates and invertebrates last shared a common ancestor more than five hundred million years ago. The appearance of Pax-6 in all animals with eyes can be explained in multiple ways. Based on the information above, which explanation is most likely? A-The Pax-6 gene is really not one gene. It is many different genes that, over evolutionary time and due to convergence, have come to have a similar nucleotide sequence and function. B-The Pax-6 gene was an innovation of an ancestral animal of the early Cambrian period. Animals with eyes or eyespots are descendants of this ancestor. C-Pax-6 in all of these animals is not homologous; it arose independently in many different animal phyla due to intense selective pressure favoring vision. D-The need for eyes has resulted in the separate evolution of Pax-6 genes.

Hawaii is the most southeastern of the seven largest islands and is also closest to the sea-floor spreading center from which the Pacific plate originates, which lies about 5600 km further to the southeast. Assuming equal sedimentation rates, what should be the location of the thickest sediment layer and, thus, the area with the greatest diversity of fossils above the oceanic crust? A-where the islands are most concentrated (highest number of islands per unit surface area) B-around the base of the island of Hawaii C-around the base of Kauai, the oldest of the large Hawaiian islands D-between the island of Hawaii and the sea-floor spreading center

Upon being formed, oceanic islands, such as the Hawaiian Islands, should feature what characteristic, leading to which phenomenon? A-major evolutionary innovations, leading to rafting to nearby continents B-adaptive radiation, leading to founder effect C-mass extinctions, leading to bottleneck effect D-a variety of empty ecological niches, leading to adaptive radiation

The duplication of homeotic (Hox) genes has been significant in the evolution of animals because it _____. A-allowed animals to survive on significantly fewer calories B-reduced morphological diversity into simpler forms of life C-caused the extinction of major groups D-permitted the evolution of novel forms

Why would gene duplication events, such as those seen in the Hox gene complex, set the stage for adaptive radiation? A-Without duplicated genes, species would be vulnerable to extinction. B-There are more copies of genes, meaning speciation had occurred by polyploidy. C-The original gene copy is the outgroup, and the new gene copies are the adaptive radiation. D-One copy of a gene can perform the original function, while other copies are available to take on new functions.

Evolution works by _____. A-"tinkering" with existing structures B-constantly increasing complexity C-converging on a particular phenotype D-molding the environment to conform to the organisms living in it E-predicting the future

The existence of evolutionary trends, such as increasing body sizes among horse species, is evidence that _____. A-evolution generally progresses toward some goal B-evolution tends toward increased complexity or increased size C-a larger volume-to-surface area ratio is adaptive in many mammals D-in particular environments, similar adaptations can be beneficial to more than one species

Prokaryotic cells are found in the domain(s) _____. A-Bacteria and Archaea B-Bacteria and Eukarya C-Bacteria and Protista D-Bacteria E-Protista and Archaea

In the five-kingdom system, prokaryotes are placed in the kingdom _____. A-Protista B-Animalia C-Fungi D-Plantae E-Monera

A human is classified in domain _____ and kingdom _____. A-Eukarya ... Fungi B-Eukarya ... Protista C-Eukarya ... Plantae D-Eukarya ... Animalia D-Bacteria ... Archaea

A rose bush is classified in domain _____ and kingdom _____. A-Eukarya ... Fungi B-Eukarya ... Protista C-Eukarya ... Plantae D-Eukarya ... Animalia E-Bacteria ... Archaea

In the five-kingdom system, which kingdom consists primarily of unicellular eukaryotes? A-Fungi B-Protista C-Plantae D-Animalia E-Monera

In the two-kingdom system, why were fungi classified in the kingdom Plantae? A-They are sedentary. B-They are heterotrophs. C-They lack cell walls. D-They are unicellular. E-They are autotrophs.

There is(are) _____ eukaryotic domain(s). A-one B-two C-three D-four E-five

Which of the following taxonomic categories contains all the others listed here? A-family B-class C-genus D-species E-order

The best classification system is that which most closely _____. A-conforms to traditional, Linnaean taxonomic practices B-reflects the basic separation of prokaryotes from eukaryotes C-unites organisms that possess similar morphologies D-reflects evolutionary history

Animals that possess homologous structures probably _____. A-have increased genetic diversity B-are not related C-are the result of similar environmental pressures in different evolutionary lineages D-evolved from the same ancestor E-are the result of convergent evolution

Systematists have used a wide variety of traits to reconstruct the phylogenies of particular groups of organisms. Which one of the following traits produces a good estimate of phylogeny? A-gross morphological traits B-biochemical traits C-molecular traits D-behavioral traits E-all of the above traits combined

Some beetles and flies have antler-like structures on their heads, much like male deer do. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of _____. A-homology B-parsimony C-a synapomorphy D-convergent evolution

Which of the following pairs are the best examples of homologous structures? A-bat wing and bird wing B-owl wing and hornet wing C-bones in the bat wing and bones in the human forelimb D-eyelessness in the Australian mole and eyelessness in the North American mole

Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser panda in the raccoon family (Procyonidae). If the molecular data best reflect the evolutionary history of these two groups, then the morphological similarities of these two species is most likely due to _____. A-possession of analogous (convergent) traits B-possession of shared primitive characters C-the inheritance of acquired characteristics D-sexual selection

What process actually increases the number of genes in an organism's genome? A-mutation B-gene duplication C-parsimony D-cladistics E-independent assortment

Which value(s) would be required to calculate how long ago the most recent ancestor of ungulates lived? I) the number of base pairs that differ among species in a certain genetic sequence II) the total number of base pairs in the genetic sequence examined III) the age of a fossil ancestor for calibration A-I B-II C-III D-I, II, and III

Which statement represents the best explanation for the observation that the nuclear DNA of wolves and domestic dogs has a very high degree of sequence homology? Dogs and wolves _____. A-belong to the same order B-are both members of the order Carnivora C-have very similar morphologies D-share a very recent common ancestor

Molecular clocks are based on the idea that _____. A-advantageous mutations arise at a constant rate B-directional selection occurs at a constant rate C-on average neutral mutations arise at a constant rate D-molecules resonate at a certain frequency that can be measured E-mutations occur once every generation