Bio 102 Test 1 Study Guide

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2. During binary fission, DNA replication begins at the ________________ and continues all the way around the circular chromosome.

origin of replication

What is the equation for hardyweinberg equilibrium?

p^2 + 2pq + q^2 = 1

if the development of reproductive organs accelerates compared to that of other organs, the sexually mature stage of a species may retain body features that were juvenile structures in ancestral species, a condition called ____

paedomorphosis

oldest to youngest periods in the cenozoic

paleogene, neogene, quaternary

In what era was the cambrian explosion?

paleozoic

in what era did the first tetrapods and insects appear?

paleozoic

a ______ group consists of an ancestral species and some, but not all, of its descendants

paraphyletic

parasites that cause disease are known as ____, many of which are prokaryotic

pathogens

The _____ of evolution shows change because the observations drawn shows change over time

pattern

6. The rapid reproduction and large population sizes of many bacterial populations mean that even a small mutation rate can lead to considerable _____________.

genetic variation

4. In theory, the two daughter cells are _______________ each other and the parent cell.

genetically identical to

what two parts consist of binomial nomenclature?

genus and epthet

The study of fossils helped geologists establish ______: a standard time scale that divides Earth's history into 4 eons and further subdivisions

geologic record

the walls of ______ bacteria have less peptidoglycan and are structurally more complex with an outer membrane that contains lipopolysaccharides

gram-negative

________ bacteria have relatively simple walls composed of a thick layer of peptidoglycan

gram-positive

sister taxa is .....

groups of organisms that share an immediate common ancestory that is not shared by any other group

the first three eons are (oldest to youngest) all around 4 billion years

hadean, archaean, proterozoic

In what eon was the origin of the earth?

hadeon

where is a prokaryotes nucleus located and what is this

nucleoid - region of cytoplasm that is not enclosed by a membrane

____ must use O2 for cellular respiration and cannot grow without it

obligate aerobes

_____ are poisoned by by O2

obligate anaerobes

What is postzygotic isolation?

occurs when fertilization has occurred but a hybrid offspring cannot develop or reproduce

a _____ group includes distantly related species but does not include their most recent common ancestor

polyphyletic

natural selection is..

A process in which individuals with certain inherited traits tend to survive and reproduce at higher rates than others

Commensalism

A relationship between two organisms in which one organism benefits and the other is unaffected

parasitism

A relationship in which one organism lives on or in a host and harms it.

What did Linneaus do for evolution?

Developed the two part (binomial) format for naming species that grouped similar species into increasingly general categories

genetic variation is...

Differences among individuals in the composition of their genes or other DNA sequences

what happens in sympatric speciation?

speciation occurs in populations that live in the same geographic area

what is frequency dependent selection?

the fitness of a phenotype depends on how common it is in the population

what is transformation?

the genotype and possibly the phenotype of a prokaryotic cell are altered by the uptake of foreign DNA from its surroundings

What is horizontal gene transfer?

the movement of genes from one genome to another through mechanisms such as exchange of transposable elements and plasmisa, viral infection, and perhaps fusion of organisms

What is speciation?

the process by which one species splits into 2 or more species

What is an exaptation?

the process in which structures originally adapted for one function take on new functions through descent with modification

fossils are ....

the remains or traces of organisms from the past

What is taxonomy?

the science of naming and classifying organisms

paleontology is....

the study of fossils

Darwin amassed evidence that descent with modification by natural selection explains the three broader observations about nature are....

the unity of life, the diversity of life, and the striking ways in which organisms are suited for life in their environments

What are prezygotic barriers?

they block fertilization from occurring

what are the tree mechanisms that bring together prokaryotic DNA from different organisms

transduction, transformation, conjugation

oldest to youngest periods in the mesozoic

triassic, jurassic, cretaceous

archaea

used to be known as bacteria but then it was discovered that they were closer to eukaryotes

________ are remnants of features that served a function in the organism's ancestors

vestigial structures

homeotic genes determine

where basic features will be arranged

Resistance genes are often carried by plasmids known as

R plasmids

What 3 Eras is the Phanerozoic Eon divided into? (oldest to youngest)

Paleozoic, mesozoic, cenozoic

What are the five conditions for Hardy-Weinberg equilibrium?

1. No mutations 2. random mating 3. No natural selection 4. Extremely large population size 5.No gene flow

What was Lamarck's hypothesis of evolution? (3 parts)

1. Parts of the body that are used extensively become larger and stronger, while those not used deteriorate 2. Inheritance of acquired traits where organisms can pass these traits down to their offspring 3. Evolution happens because organisms have an innate drive to become more complex

The age of fossils can sometimes be determined by radiometric dating, which is based on the constant rate of decay of radioactive isotopes. The time required for half of a radioactive isotope to decay is called the half-life of that isotope. For example, the isotope carbon-14 has a half-life of 5,730 years. Suppose it is determined that a fossilized leaf contains 12.5% of the carbon-14 that was present when the fossil formed. How old is the fossil? Express your answer numerically.

1.72 x 10^4 years

Plant species F has a diploid number of 8. Plant species G has a diploid number of 10. What would be the diploid number of an allopolyploid hybrid of species F and species G? Enter your answer as a whole number.

What is Hardy-Weinberg equilibrium?

states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.

strata is ....

superimposed layers of rock from sediment

Each branch tip on a phylogenetic tree represents a specific group of organisms known as a(n) _____

taxon

The named taxonomic unit at any level of the hierarchy is called a _____

taxon

In phylogenetic trees, we should not assume that the _____ on a phylogenetic tree evolved from the _____ next to it

taxon, taxon

What is macroevolution?

the broad pattern of evolution above the species level

genetic recombination is...

the combining of DNA from two sources

What is reproductive isolation?

the existence of biological factors (barriers) that impede two species from producing viable, fertile offspring

a shared derived character is...

An evolutionary novelty that is unique to a particular clade.

What are the three domains?

Bacteria, Archaea, Eukarya

Cells containing the F plamid (F+ cells) function as what

DNA donors during conjugation

Microevolution is...

Change in allele frequencies in a population over generations.

What is nitrogen fixation?

Converts gaseous N2 to ammonia

who mostly developed paleontology?

Cuvier

what is conjugation?

DNA is transferred between two prokaryotic cells that are temporarily joined, usually in the same species. One cell donates the DNA, one cell receives it via the "mating bridge"

cells lacking the F factor (F- cells) function as what

DNA recipients during conjugation

What did Hutton propose?

Earth's geologic features could be explained by gradual mechanisms (like valleys being formed by rivers)

The ability to form pili and donate DNA during conjugation results from the presence of a particular piece of DNA called the ____. It can exist as either a plasmid or a segment of DNA within the chromosome

F factor

The F factor in its plasmid form is called the

F plasmid

_______ had been colonized by organisms that had strayed from South America and then diversified, giving rise to new species on the various islands

Galapagos islands

The ____ was developed by Danish physician Hans Gram where scientists can categorize many bacterial species according to differences in cell wall composition

Gram stain

What are the five kingdoms?

Monera, Protista, Fungi, Plantae, Animalia

What did Aristotle believe about evolution?

That species were fixed (unchanging) and that life-forms could be arranged on a ladder of increasing complexity (scala naturae)

Where did Darwin publish his hypothesis?

The Origin of Species

How is an endospore formed?

The bacterium copies it's chromosomes and produces a wall around the copy

what is phylogeny?

The evolutionary history of a species or group of related species

convergent evolution is .....

The independent evolution of similar features in different lineages

What did Lyell believe?

The same geologic processes are operating today as in the past, and at the same rate

what is gene flow?

The transfer of alleles into or out of a population due to the movement of fertile individuals or their gametes

a key feature of nearly all prokaryotic cells

Their cell wall, which maintains cell shape, protects the cell, and prevents it from bursting in a hypotonic environment

Who produced an almost identical process to that of Darwin's?

Wallace

A biologist doing a long-term study on a wild spider population observes increased variation in silk thickness. Which of the following processes is the most likely to be affecting the spider population? a. disruptive selection b. genetic drift c. stabilizing selection d. directional selection

A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that _____. See Concept 22.3 (Page) View Available Hint(s) a. embryos of dissimilar organisms, such as sharks and humans, resemble each other b. all animals develop similar embryonic gills c. mutations have a far more dramatic effect on embryos than on adult organisms d. the more advanced the animal, the more slowly it develops e. the embryological development of many plants and animals is almost identical

A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that _____. See Concept 22.3 (Page) View Available Hint(s) a. embryos of dissimilar organisms, such as sharks and humans, resemble each other b. the more advanced the animal, the more slowly it develops c. mutations have a far more dramatic effect on embryos than on adult organisms d. the embryological development of many plants and animals is almost identical e. all animals develop similar embryonic gills

A female fly, carrying fertilized eggs, is hypothetically swept by high winds to an island far out to sea. She is the first and only fly to arrive on this island. Thousands of years later, her numerous descendents occupy the island and have overlapping geographic ranges. They are separated into several different species with different foods, mouthparts, egg-laying sites, and egg shapes. 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. Which of these fly organs, as they exist in the description, best illustrates an exaptation? a. the halteres b. the eggs c. the wings in the ancestral species d. the mouthparts

A female fly, full of fertilized eggs, is swept by high winds to an island far from the mainland. She is the first, and only, fly to arrive on this island. Thousands of years later, her numerous offspring occupy the island, but none of them resembles her. There are, instead, several species and their geographic ranges overlap. Each species eats a different kind of food. None of the species can fly and the balancing organs of males differ among species and are now used in courtship displays. Fly species W produces fertile offspring with species Y, but not with species X or Z. Furthermore, X and Z do not hybridize. Which of the following statements about species W and Y is most likely to be accurate? a. Species W and Y may fuse into a single species if their hybrids remain fertile over the course of many generations. b. Species W and Y have genomes that are too dissimilar for successful meiosis to occur in hybrid flies. c. Species W and X have more genetic similarity with each other than either does with the other two species. d. Species W and Y will both be selected to avoid mating with each other.

A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 25% of the animals display a recessive trait (A2A2), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants.What is the most reasonable conclusion that can be drawn from the fact that the frequency of the recessive trait (A2A2) has not changed over time? a. The two phenotypes are about equally adaptive under laboratory conditions. b. There has been a high rate of mutation of allele A1 to allele A2. c. There has been sexual selection favoring allele A2. d. The genotype A1A1 is lethal.

What usually happens to the recipient cell following conjugation with an Hfr cell? a. The recipient cell remains an F- cell. b. The recipient cell becomes an Hfr cell. c. The recipient cell remains an F+ cell. d. The recipient cell may become either an F+ or an Hfr cell.

A population of dark-eyed junco birds became established near the California coastline, many miles from the junco's normal habitat in the mixed-coniferous temperate forests in the mountains. Juncos have white outer tail feathers that the males display during aggressive interactions and during courtship displays. Males with more white in their tail are more likely to win aggressive interactions, and females prefer to mate with males with more white in their tails.The coastal male junco population tails were, on average, 36% white; whereas the tails of males from the mountain populations averaged 40-45% white. Which of the following factors is the most likely original cause of the difference between the populations if the trait is inherited? a. a founder effect in the coastal population b. a bottleneck effect in the coastal population c. gene flow between populations d. mutations in the coastal population

A proficient engineer can easily design skeletal structures that are more functional than those currently found in the forelimbs of such diverse mammals as horses, whales, and bats. Which of the following statements best explains why the actual forelimbs of these mammals do not seem to be optimally arranged? a. Natural selection is generally limited to modifying structures that were present in previous generations and in previous species. b. Natural selection has not had sufficient time to create the optimal design in each case, but will do so given enough time. c. In many cases, phenotype is determined by genotype and the environment. d. Although we may not consider the fit between the current skeletal arrangements and their functions excellent, we should not doubt that natural selection ultimately produces the best design.

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. Which of the following effects is most likely to result from the immigration? a. a decrease in birds' adaptation to the new food plants b. an increase in birds' adaptation to the new food plants c. another round of incipient speciation d. an increase in the speed of speciation

According to the concept of punctuated equilibrium, the "sudden" appearance of a new species in the fossil record means that ________. a. speciation occurred rapidly in geologic time b. the species will consequently have a relatively short existence compared with other species c. the species is now extinct d. speciation occurred in one generation

Adult male humans generally have deeper voices than do adult female humans. Which of the following processes was most likely occurring given that the fossil records of apes and humans alike show a trend toward decreasing larynx size in adult females and increasing larynx size in adult males? a. sexual dimorphism was evolving over time in these species b. selection was acting more directly upon genotype than upon phenotype c. intrasexual selection seems to have occurred in these species d. stabilizing selection was occurring in these species concerning larynx size

An adaptation is __________. View Available Hint(s) a. a trait that gives an organism a reproductive advantage in the current environment b. the cause of natural selection c. a trait that gives rise to a new species d. an individual's attempt to conform to its environment e. All of the listed answers are correct.

Are changes to an organism's physical environment likely to result in an evolutionary change? a. A trait that is favorable in one environment can be less successful or even harmful in another environment. Thus, if a feature of the environment changes, selective pressures may change as well. b. Changes in the physical environment cannot influence evolution because the physical environment is not connected to genetic information, which is the one affected by natural selection. c. Changes to the physical environment are not likely to result in an evolutionary change because natural selection deals only with living organisms. It favors or goes against their particular traits and does not deal with nonliving aspects. d. Evolutionary changes may be caused by the physical environment of an organism because physical aspects are the only elements that affect species' fitness.

Carolus Linnaeus believed that species remained fixed in the form in which they had been created. Which of the following concepts are inconsistent with Linnaeus's model of classification? a. phylogenies b. taxonomy c. nested, increasingly inclusive categories of organisms d. a hierarchical classification scheme

Cotton-topped tamarins are small primates with tufts of long white hair on their heads. While studying these creatures, a scientist noticed that males with longer hair get more opportunities to mate and that they father more offspring than males with shorter hair. Which of the following possible studies would be the best design for testing if longer hair is an adaptive trait? Assume that hair length is a trait that is inherited. a. Capture a group of males with long hair at random, and cut the hair very short in half of the males; then, compare the number of matings of males with their hair left unchanged vs. males with shortened hair. b. Follow at least ten troops of tamarins and compare the number of matings by males that live in large groups vs. those that live in small groups. c. From long-term observational records, determine the ages of males and then compare the number of matings by males of different ages. d. Follow at least 20 troops of tamarins and compare the number of matings by males that live high in trees vs. those that live on the ground.

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that a. humans and chimpanzees share a relatively recent common ancestor. b. convergent evolution led to the DNA similarities. c. humans evolved from chimpanzees. d. chimpanzees evolved from humans.

Different finch species have beaks of different shapes and sizes. What do these beak differences tell us? a. Different finch beak shapes are evidence that finch species adapted to different environments over many generations. b. Different finch beak shapes are evidence that individual birds changed their beaks so that they could feed efficiently. c. Different finch beak shapes are evidence that several finch species with different beak types came to the Galápagos Islands from the mainland. d. Different finch beak shapes are evidence that all Galápagos finches share a common ancestor.

Eukaryotes that are not closely related and that do not share many anatomical similarities can still be placed together on the same phylogenetic tree. Which of the following approaches would be most appropriate for doing this? a. by comparing their homologous genes that are highly conserved b. by comparing their plasmids c. by comparing their homologous genes that are poorly conserved d. by comparing their mitochondrial genomes

Evolutionary biologists have developed a phylogeny for a group of mammals based on bone structure. Which of the following statements best predicts the phylogeny for the same group of mammals based on similarities and differences in the structure of a particular enzyme? a. The phylogeny would be different than the phylogeny based on bone structure. b. The phylogeny would be the same as the phylogeny based on bone structure. c. The amino acid sequence for this particular enzyme would be identical in all species. d. No prediction regarding the phylogeny could be made.

Fossil evidence indicates that some dinosaurs had feathers. If birds are indeed descended from dinosaurs, feathers are what kind of character? View Available Hint(s) a. shared ancestral character b. polyphyletic character c. cladistic character d. analogous character e. shared derived character

Fossilized stromatolites a. resemble structures formed by bacterial communities that are found today in some shallow marine bays. b. provide evidence that plants moved onto land in the company of fungi around 500 million years ago. c. contain the first undisputed fossils of eukaryotes. d. formed around deep-sea vents.

How does the term "lactase persistent" relate to the term "lactose tolerant"? a. A lactase-persistent person is lactose tolerant. b. Lactose tolerance has nothing to do with lactase-persistence. c. A lactase-persistent person is lactose intolerant.

How long does it take new species to form on Earth? a. The time required varies considerably b. .Speciation no longer takes place on Earth. c. millions of years

Identify the pair of homologous structures. a. Maple leaf and oak leaf b. Maple leaf and maple seed c. Neither of the above; plants do not have homologous structures.

If additional DNA sequence evidence shows that yeast genes for synthesizing proteins are more similar to protein-synthesizing genes in bacteria than those in archaea, what would a systematist do with the current phylogeny? a. redraw the phylogeny to show eukaryotes sharing a more recent common ancestor with bacteria than archaea b. redraw the phylogeny to show more recent common ancestry between archaea and yeast than between eukaryotes and archaea c. retain the phylogeny that shows a more recent common ancestor between bacteria and archaea d. retain the phylogeny that shows a more recent common ancestor between eukaryotes and archaea

If individuals tend to mate within a subset of the population, there is ________. a. no random mating b. no genetic drift c. no selection d. abundant gene flow

If you were using cladistics to build a phylogenetic tree of cats, which of the following organisms would be the best outgroup? a. wolf b. lion c. domestic cat d. leopard

If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the best outgroup? a. wolf b. lion c. leopard d. domestic cat

Imagine that you are an explorer who has discovered an isolated land mass in the middle of the Pacific Ocean. You find a predator that resembles a North American wolf except that it lays eggs. You name it the "mid-ocean wolf." The physical similarity between the mid-ocean wolf and the North American wolf is most likely due to which of the following factors? a. natural selection that favors similar traits for organisms with similar ecological roles b. inheritance of the characteristics from a recent common ancestor c. natural selection that favors the evolution of homologous structures d. similarities in prey species

In 1986, a nuclear power accident in Chernobyl, USSR (now Ukraine), led to high radiation levels for miles surrounding the plant. The high levels of radiation caused elevated mutation rates in the surviving organisms, and evolutionary biologists have been studying rodent populations in the Chernobyl area ever since. Which of the following events most likely occurred in the rodent populations following the accident? a. Mutation led to increased genetic variation. b. Mutation caused major changes in rodent physiology over time. c. Mutation caused the fixation of new alleles. d. Mutation caused genetic drift and decreased fitness.

In Europe, there is a long narrow hybrid zone, shown in red on the map, between the high-altitude habitat of the yellow-bellied toad and the lowland habitat of the fire-bellied toad. Despite this, there is little gene flow between the two species. Select the correct explanation. a. Hybrids have poor survival and reproduction and thus produce few viable offspring with members of either parent species. b. Toads mate only with their own kind in order to avoid producing unhealthy hybrid young. c. Yellow-bellied toads and fire-bellied toads are two different species.

In a bell-shaped curve, the x-axis (horizontal direction) of the graph represents which of the following? View Available Hint(s) a. The value of a particular characteristic; characteristics of an organism can include such traits as size and color. b. The number of individuals c. Time

What are stromatolites?

are layered rocks that form when certain prokaryotes bind thin films of sediment together

In the United States today, about half of the corn crop is genetically engineered with a protein that is toxic to corn borers, an insect pest of corn. Which of the following conditions would be necessary for evolution of resistance to the toxic protein to occur in the corn borer? View Available Hint(s) a.The corn borer must have or generate (by mutation) heritable variation in resistance to the toxic protein. The resistant corn borers must survive better or reproduce more than nonresistant corn borers. b. The corn borer must lack variation in resistance to the toxic protein. c. The corn borers must experience no success in their ability to survive or reproduce. d. The corn borers must experience unlimited success in their ability to survive or reproduce.

In the projected video showing the growth of bacteria, why did the bacteria grow up to the edge of the area with antibiotics, pause, then continue to grow across the area with antibiotics? a. A few bacteria experienced random mutations in their DNA, which allowed some of them to grow even though antibiotics were present. b. The bacteria mutated as a survival response to the presence of antibiotics, enabling the bacteria to become resistant to the antibiotics. c. Researchers added antibiotic resistant bacteria to the culture, so that the bacteria would continue to grow across the area with antibiotics. d. The antibiotics caused mutations in the DNA of the bacteria, making them resistant to the antibiotics.

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.

In those parts of equatorial Africa where the malaria parasite is most common, the sickle-cell allele constitutes 20% of the β hemoglobin alleles in the human gene pool.In the United States, the parasite that causes malaria is not present, but the sickle cell allele is present in many African-Americans whose ancestors were from equatorial Africa. Which of the following processes are most likely acting on the sickle-cell allele in the United States, and in equatorial Africa? a. directional selection in the United States; stabilizing selection in equatorial Africa b. disruptive selection in the United States; stabilizing selection in equatorial Africa c. stabilizing selection in the United States; disruptive selection in equatorial Africa d. directional selection in the United States; disruptive selection in equatorial Africa

In which country would you most likely find a higher incidence of lactase persistence? a. in a Scandinavian country where people historically raised dairy cattle and made cheese b. in an Asian country where people historically did not raise cattle c. in a country in southern Africa where people historically have not consumed many dairy products d. all of the above areas should have an equal incidence of lactase persistence

Insect wings may have begun to evolve as lateral extensions of the body that dissipated heat for thermoregulation. When they had become sufficiently large, these extensions became useful for gliding through the air. Additional selection resulted in refinement as flight-producing wings. If this hypothesis is correct, modern insect wings would be an example of which of the following? a. exaptation b. mutation c. loss of Hox genes in the evolution of new forms d. adaptive radiation

Iridium is a component of cosmic dust that rains down upon the earth at a constant rate. Why did Luis Alvarez suggest measuring iridium levels in the K-T boundary? a. He was looking for a way to determine how quickly the layer had been deposited. b. He hypothesized that the layer was caused by a supernova explosion. c. He hypothesized that the layer was caused by an asteroid impact.

James Hutton and Charles Lyell provided which of the following ideas that paved the way for Darwin's thinking? a. the surface features of Earth were formed slowly and gradually and the geological processes are still at work b. the surface features of Earth were formed by catastrophic events and those events are still occurring c. the surface features of Earth were formed gradually and the fossil record showed that species have evolved d. the surface features of Earth were formed by catastrophic events and the fossil record showed that species have evolved

Life arose during the _____. a. Precambrian b. Cenozoic c. Triassic d. Paleozoic e. Mesozoic

Many species of snakes lay eggs. However, in the forests of northern Minnesota, where the growing season is short, only live-bearing snake species are present. Which of the following processes most likely resulted in the differences in snake reproduction? a. species selection b. goal direction in evolution c. sexual selection d. natural selection leading to exaptations

Most Swiss starlings (birds) produce four to five eggs in each clutch. Starlings producing more or less eggs have reduced fitness. Which of the following terms best describes this situation? a. stabilizing selection b. sexual selection c. disruptive selection d. directional selection

Most modern animal phyla evolved during the _____ era. a. Paleozoic b. Cenozoic c. Mesozoic d. Precambrian

One population of a species has 25 individuals, all with genotype AAAA; a second population of this species has 40 individuals, all with genotype aaaa. Assume that these populations live far apart but in similar environmental conditions. Based on this information, the observed genetic variation most likely resulted from a. genetic drift. b. gene flow. c. directional selection. d. nonrandom mating.

Phylogeny is the evolutionary history of related groups of organisms. Organisms are grouped into taxa based on homologous characteristics, shared traits that result from common ancestry. Which statement is true? a. The term "monophyletic" refers to a taxon that includes an ancestral species and all of its descendants. b. Homologous structures look the same and serve the same function, but they differ in evolutionary origin and structure. c. Ancestral traits are always simpler than derived traits.

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

Reptiles first appeared during the _____ era. a. Paleozoic b. Triassic c. Mesozoic d. Cenozoic e. Jurassic

Restriction enzymes in bacteria protect the bacteria from successful attack by bacteriophages, whose genomes can be degraded by the restriction enzymes. The bacterial genomes are not vulnerable to these restriction enzymes because bacterial DNA is methylated. This situation selects for bacteriophages whose genomes are also methylated. As new strains of resistant bacteriophages become more prevalent, they in turn select for bacteria whose genomes are not methylated and whose restriction enzymes instead degrade methylated DNA. Which of the following outcomes is most likely to occur over the course of evolutionary time? a. Methylated and nonmethylated strains should be maintained among both bacteria and bacteriophages, with ratios that vary over time. b. Methylated DNA should become fixed in the gene pools of bacteriophages. c. Nonmethylated DNA should become fixed in the gene pools of bacteriophages. d. Methylated DNA should become fixed in the gene pools of bacterial species.

Seed plants first appeared during the _____. a. Paleozoic b. Triassic c. Mesozoic d. Cenozoic e. Jurassic

Select the correct statement about phylogenetic trees. a. Phylogenetic trees may expand quickly to maximum width and then narrow over time. b. Phylogenetic trees always show increased branching, representing increased diversity over time. c. All phylogenetic trees are similarly shaped.

Select the correct statement describing sympatric speciation. a. Sympatric speciation can occur in a single generation. b. Sympatric speciation has never been observed in nature. c. Sympatric speciation is always initiated by geographic isolation of two populations.

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, which develop from similar embryonic tissues. These structural similarities are an example of ________. a. homology b. the evolution of similar appearance as a result of common function c. the evolution of common structure as a result of common function d. convergent evolution

Studies of Neanderthal DNA revealed that there are more similarities to non-African DNA than reference sequences from West Africans. Additionally, scientists found that Neanderthal DNA is as closely related to East Asians as to Europeans. These patterns indicate that interbreeding occurred before human migration further east. Which evolutionary force most likely generated these results? a. gene flow b. adaptive evolution c. genetic drift d. nonrandom mating

The Precambrian time began at least _____ million years ago. a. 4,600 b. 570 c. 245 d. 65 e. 25

The chemoheterotroph Proteus vulgaris is a rod-shaped bacterium classified with _____. a. proteobacteria b. chlamydias c. spirochetes d. gram-positive e. bacteria cyanobacteria

The different finch species found on the Galápagos Islands probably arose as a result of _____. a. adaptive radiation b. mass extinction c. paedomorphosis d. gene flow e. artificial selection

The earliest organisms were most likely __________. View Available Hint(s) a. Prokaryotic b. protocells c. Eukaryotic d. plants and fungi e. Multicellular

The half-life of carbon-14 is about 5,730 years. A fossil that has 1/16 of the normal proportion of carbon-14 to carbon-12 should be about how many years old? a. 22,900 b. 11,200 c. 2,800 d. 16,800

The higher the proportion of loci that are "fixed" in a population, the lower is that population's ________. nucleotide variability and average a. heterozygosity b. average heterozygosity c. nucleotide variability d. chromosome number

The kingdom Monera was dismantled because of which of the following reasons? a. Monera contained organisms from other domains b. The Monera, as originally constituted, contained both plants and animals. c. The Monera, as originally constituted, was monophyletic. d. Some Monera contained nuclei in their cells.

The largest unit within which gene flow can readily occur is a a. species. b. hybrid. c. genus. d. population.

The original habitat of the North American maggot fly, Rhagoletis pomonella, was native hawthorn trees. About 200 years ago, some populations colonized newly introduced apple trees. The two populations are still classified as subspecies, but sympatric speciation is under way. What has contributed to incipient speciation in the maggot fly? a. Because apples mature more quickly than hawthorn fruit, the apple-feeding flies have been selected for more rapid development. b. Apple maggot flies try to avoid mating with hawthorn maggot flies. c. Maggot flies that feed and lay eggs on apples have gradually become adapted to this fruit.

The oxygen revolution changed Earth's environment dramatically. Which of the following took advantage of the presence of free oxygen in the oceans and atmosphere? a. the evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules b. the evolution of chloroplasts after early protists incorporated photosynthetic cyanobacteria c. the evolution of photosynthetic pigments that protected early algae from the corrosive effects of oxygen d. the persistence of some animal groups in anaerobic habitats

The prokaryotic flagellum is a complex structure consisting of several dozen different proteins. Which of the following statements best describes the origin of flagella in prokaryotes? a. Ancestral versions of this protein assemblage were either less functional or had different functions than modern prokaryotic flagella. b. The need for more complex structure must have driven evolution. c. Flagella could not have arisen by evolution because the structure is too complex to have evolved gradually. d. Natural selection cannot account for the evolution of the prokaryotic flagellum.

The prokaryotic organisms most likely to be found living in salt ponds are the __________. View Available Hint(s) a. extreme halophiles b. extreme thermophiles c. Korarchaeota d. methanogens e. extremophiles

organisms that need only CO2 or related compounds as a carbon source are called

autotrophs

The term convergent evolution is most applicable to which of the following characteristics? a. the presence of an opposable thumb in humans and chimpanzees b. the fur that covers Australian moles and North American moles c. the layer of fat found under the skin of mammals such as dolphins and polar bears d. the bones of bat forelimbs and the bones of bird forelimbs

The wing of a bat is homologous to the _____ of a whale. a. flipper b. tail c. rib cage d. baleen e. blowhole

There is(are) _____ eukaryotic domain(s). a. one b. two c. three d. four e. five

Three-spined stickleback fish (Gasterosteus aculeatus) show substantial genetic variation in gill-raker length related to differences in their diets. Longer gill rakers appear to function better for capturing open-water prey, while shorter gill rakers function better for capturing shallow-water prey. Which of the following types of selection is most likely to be found in a large lake (open water in the middle and shallow water around the sides) with a high density of these fish? a. disruptive selection b. stabilizing selection c. sexual selection d. directional selection

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. View Available Hint(s) a. True b. False

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. View Available Hint(s) a. True b. False

True or false? Data showing that the Bacteria were the first lineage to diverge from the common ancestor of all living organisms suggest that the Archaea and Eukarya are more closely related to each other than they are to the Bacteria. View Available Hint(s) a. True b. False

True or false? It would be difficult to assess whether the drug-susceptible or drug-resistant phenotype in a population of Mycobacterium tuberculosis was more fit in an environment without antibiotics. View Available Hint(s) a. True b. False

True or false? The Hardy-Weinberg model makes the following assumptions: no selection at the gene in question; no genetic drift; no gene flow; no mutation; random mating. a. True b. False

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 in captivity, they interbreed and produce fertile young whose appearance is intermediate between the two parents. In the wild, the two populations remain separate as a result of which of the following factors? a. habitat isolation b. temporal reproductive isolation c. lack of hybrid viability d. behavior isolates reproductive activities

Two species of frogs belonging to the same genus occasionally mate, but the embryos stop developing after a day and then die. Which of the following mechanisms keep the species separate? a. reduced hybrid viability b. reduced hybrid fertility c. gametic isolation d. hybrid breakdown

Two species of fruit flies occur on the volcanic, equatorial West African island of Sao Tome that rose from the Atlantic Ocean 14 million years ago. Drosophila santomea occurs only on at higher elevations, while D. yakuba inhabits the lowlands. D. yakuba also occurs on the African mainland. On Sao Tome a hybrid zone between the two species exists at middle elevations. Hybrid males, but not females, are sterile, and hybrids are greatly outnumbered by D. santomea. Studies of the two species' nuclear genomes reveal that D. yakuba on the island is more closely related to mainland D. yakuba than to D. santomea (2n = 4 in both species). Using this information, which of the following phenomena is the best initial hypothesis for how D. santomea descended from D. yakuba? a. habitat differentiation b. allopolyploidy c. sexual selection d. autopolyploidy

What did Wallace conclude from observing that the bones in manatee flippers look similar to the bones in a human arm and hand? a. Manatees' arm and finger bones are evidence that manatees share a common ancestor with land mammals. b. Manatees were specially created in their current form, including the arm and finger bones inside their flippers. c. Manatees use their flippers like humans use their hands. d. Manatee finger bones must have an important function, necessary for the animal's survival.

What did researchers discover about the genetic mutation causing lactase persistence? a. It is found in a regulatory region (a "switch") upstream of the lactase gene. b. It is the same mutation in European and African populations. c. The mutation affects different genes in European and African populations. d. It is found in the coding region of the lactase gene on chromosome 2.

What is the meaning of Darwin's expression "descent with modification"? a. Descent with modification refers to evolutionary change over time. b. Descent with modification refers to natural selection. c. Descent with modification refers to the partial resemblance of offspring to their parents.

What is the only evolutionary mechanism that consistently leads to adaptive evolution? View Available Hint(s) a. natural selection b. gene flow c. the bottleneck effect d. neutral variation e. genetic drift

What kind of evidence has recently made it necessary to assign the prokaryotes to either of two different domains, rather than assigning all prokaryotes to the same kingdom? a. rRNA genes b. morphological c. mtDNA d. ecological

What process actually increases the number of genes in an organism's genome? View Available Hint(s) a. gene duplication b. parsimony c. cladistics d. mutation e. independent assortment

What was the critical piece of evidence that supported the hypothesis that an asteroid struck Earth 65 million years ago? a. the Chicxulub crater in Mexico b. tsunami deposits in the Brazos River Basin in Texas c. gravitational anomalies on the Yucatan peninsula, from surveys done for oil exploration d. spherules and shocked quartz in Haiti

What would be the ploidy of the viable gametes produced by a tetraploid individual if nondisjunction of all chromosomes occurred in meiosis I? View Available Hint(s) a. Tetraploid b. Triploid c. Haploid d. Diploid

When dark-colored fur gives mice a 1% competitive advantage and 1% of the population begins with dark fur, in about 1000 years, 95% of the population will have dark fur. Which of the following statements is true? a. If dark-colored rock pocket mice had a competitive advantage of 0.1%, it would take longer for 95% of the population to have dark fur. b. Dark-colored rock pocket mice, in this population, have fewer offspring than light-colored rock pocket mice. c. If dark-colored mice had a competitive advantage of 10%, it would take longer for 95% of the population to have black fur. d. If dark-colored mice had a competitive advantage of 5%, it would take longer for 95% of the population to have black fur.

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.

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. The species became separated by convergent evolution. c. India is in the process of separating from the rest of Asia. d. The climates of the two regions are similar.

Which of the following are basic components of the Hardy-Weinberg model? View Available Hint(s) a. Frequencies of two alleles in a gene pool before and after many random matings b. Allele frequencies in a subset of the population c. Allele frequencies, number of individuals in the population d. Allele frequencies, phenotype frequencies

Which of the following characteristics is a postzygotic barrier that prevents hybrids between two species from producing offspring? a. hybrid breakdown b. increased hybrid fertility c. hybrid gamete isolation d. increased hybrid vulnerability

Which of the following could cause DNA from the main chromosome of a donor cell to be incorporated into the main chromosome of the recipient cell? a. conjugation between an Hfr cell and an F- cell b. conjugation between an F+ cell and an F- cell c. conjugation between two F- cells d. conjugation between two F+ cells

Which of the following evolutionary forces consistently results in adaptive changes in allele frequencies? View Available Hint(s) a. Selection b. Inbreeding c. Mutation d. There is no evolutionary force that results in adaptive changes in allele frequencies.

Which of the following evolutionary forces could create new genetic information in a population? View Available Hint(s) a. Mutation b. Nonrandom mating c. Genetic drift d. Selection

Which of the following factors is the primary criterion for determining species boundaries when applying the biological species concept? a. gene flow b. niche differences c. geographic isolation d. morphological similarity

Which of the following has been shown to cause speciation most rapidly? View Available Hint(s) a. autopolyploidy b. sexual selection c. punctuated equilibrium d. differential resource exploitation e. hybridization

Which of the following is true of microevolution? View Available Hint(s) a. it is the kind of evolution that can change the relative abundance of a particular allele in a gene pool over the course of generations b. it is evolution that results in the origin of small numbers of new species c. it is evolution that influences only a small subset of the populations that comprise a species d. it is evolution that involves only tiny changes to DNA, such as point mutations, producing only small (if any) changes to phenotype e. it is evolution that is restricted to individual organisms

Which of the following observations most strongly supports the common origin of all life on Earth? a. All organisms use essentially the same genetic code. b. All organisms require energy. c. All organisms reproduce. d. All organisms show variation that is inherited.

Which of the following observations would provide evidence supporting Lamarck's proposed evolutionary mechanism of "inheritance of acquired characteristics"? a. a decrease in tail length in dogs after 20 generations of dogs that had their tails docked (cut off) as puppies b. an increase in the length of giraffes' necks after trees in the area decreased in height c. a decrease in the size of the tails of salamanders in a population that immigrated into a cave 20 generations earlier d. an increase in average speed of deer on an island when the amount of food increased

Which of the following outcomes is the most likely evolutionary effect of duplication of homeotic Hox genes? a. It permitted the evolution of novel forms. b. It reduced morphological diversity of simple forms of life. c. It caused the extinction of major groups. d. It allowed the reversal of the head-tail orientation of animals.

Which of the following processes would, if it had acted upon a gene, prevent this gene from acting as a reliable molecular clock? a. natural selection b. neutral mutations c. mutations within introns d. genetic drift

1. Binary fission is a form of _____________ because a single individual is the sole parent and passes copies of all its genes to its offspring.

asexual reproduction

Which of the following statements about descent with modification is true? a. Over time, evolution by natural selection in different environments causes organisms to accumulate differences from their ancestors. b. Two species descended from a common ancestor that lived in the distant past will not share any characteristics. c. All similarities between organisms result from descent from a common ancestor. d. Organisms that share a more recent common ancestor are likely to be more different from one another than are organisms that share a distant common ancestor.

Which of the following statements about reinforcement is true? View Available Hint(s) a. Reinforcement is a type of natural selection. b. Reinforcement decreases the morphological difference between two incipient species. c. Reinforcement is also called dispersive selection. d. Reinforcement increases the number of intermediate phenotypes.

Which of the following statements about vestigial structures is accurate? a. A vestigial structure in species A can be homologous to a functional structure in species B. b. A vestigial structure in species A did not have a function in past ancestors c. A vestigial structure in species A is likely an example of convergent evolution with a structure in species B. d. A vestigial structure in species A can be analogous to a functional structure in Species B.

Which of the following statements best describes Darwin's theory of evolution by natural selection? a. Darwin's theory emphasized that populations vary and change over time. b. Darwin's theory proved that individuals acclimated to their environment over time. c. Darwin's theory was the first to propose that species changed over time. d. Darwin's theory was the first to describe the ideas of special creation.

Which of the following statements best describes the rationale for applying the principle of maximum parsimony in constructing phylogenetic trees? a. For trees based on morphology, the most parsimonious tree requires the fewest evolutionary events. b. The principal of analogy validates the principle of parsimony. c. Parsimony allows the researcher to "root" the tree. d. The outgroup roots the tree, allowing the principle of parsimony to be applied.

Which of the following statements best describes unity within a species? a. Members of a given species have the potential to interbreed in nature and produce viable, fertile offspring. b. Members of a given species can be distinguished by similarity in body shape and other structural features. c. A species is described in terms of its interaction with living and non-living environment. d. The DNA sequence lacks similarities among individuals.

Which of the following statements describes the evolution by natural selection of Mycobacterium tuberculosis bacteria in their new environment? View Available Hint(s) a.The drug-resistance trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin. b. The drug-resistance trait is an adaptation to the environment in which human hosts travel worldwide and are exposed to new strains of bacteria. c. The drug-susceptibility trait is an adaptation to the environment of antibacterial soaps. d. The drug-susceptibility trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin.

Which of the following statements explains why paralogous genes can diverge from each other within the same gene pool, whereas orthologous genes diverge only after gene pools are isolated from each other? a. having an extra copy of a gene permits modifications to the copy without loss of the original gene product b. polyploidy is a necessary precondition for the occurrence of sympatric speciation in the wild c. paralogous genes can occur only in diploid species, thus they are absent from most prokaryote d. shaving multiple copies of genes is essential for the occurrence of sympatric speciation in the wild

Which of the following statements is accurate with regard to a population in Hardy-Weinberg equilibrium? a. Allele frequencies should not change from one generation to the next. b. Individuals within the population are evolving. c. Two alleles are present in equal proportions. d. Natural selection, gene flow, and genetic drift are acting equally to change allele frequencies.

Which of the following statements is most consistent with data obtained from the fossil record? a. Older strata carry fossils that differ greatly from living organisms. b. Organisms have an innate drive to increase in complexity. c. Unused body parts decrease in size. d. Geologic changes occur quickly on Earth.

Which of the following statements most accurately describes a difference between the current atmosphere and that of early Earth? a. Compared to today, early Earth had an atmosphere richer in gases released from volcanic eruptions. b. Compared to today, early Earth experienced less high-energy radiation from the sun. c. Compared to today, early Earth had an atmosphere with greater quantities of ozone. d. Compared to today, early Earth had a less oxidizing atmosphere.

Which of the following typically produces a recombinant F+ recipient cell? a. conjugation between an F+ cell and an F- cell b. conjugation between two F- cells c. conjugation between two Hfr cells d. conjugation between an Hfr cell and an F- cell

Which process occurred frequently in the early history of the three domains on Earth, and makes determining phylogenetic relationships of that time difficult? View Available Hint(s) a. horizontal gene transfer b. binary fission c. meiosis d. mitosis e. alternative RNA splicing

Which statement about natural selection on early Earth is correct? a. Natural selection could act on a population of proto-cells on early Earth, selecting for those that were stable and had self-replicating, catalytic RNA that allowed them to grow and divide to produce similar daughter proto-cells. b. Natural selection acted on populations of proto-cells on early Earth in order to make them more like modern living cells that have DNA as their genetic material. c. Natural selection could only act on populations of living organisms that had DNA as their genetic material.

Your professor wants you to construct a phylogenetic tree of a type of plant called orchids. She gives you tissue from seven orchid species and one lily plant. What is the most likely reason she gave you the lily? a. to serve as an outgroup b. to see if the lily is an ancient orchid species c. to demonstrate likely genetic similarities d. to see if the lily and the orchids show all the same shared derived characters

_____ were the dominant vertebrate life form during the Mesozoic era. a. Dinosaurs b. Mammals c. Fish d. Birds e. Amphibians

_____ were the dominant vertebrate life form during the Paleozoic era. a. Amphibians b. Reptiles c. Sponges d. Dinosaurs e. Mammals

what is a Hfr cell?

a cell with the F factor built into its chromosome that acts as donor during conjugation with an F- cell and when chromosomal DNA from an Hfr cell enters an F- cell, homologous regions may align, allowing segments of DNA to be exchanged

What is sexual dimorphism?

a difference in secondary sexual characteristics between males and females of the same species

what is taxis

a directed movement toward or away from a stimulus

what is systematics?

a discipline focused on classifying organisms and determining their evolutionary relationships

What is a population?

a group of individuals of the same species living in the same area and interbreed, producing fertile offspring

What is a species?

a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring.

What is sexual selection?

a process in which individuals with certain inherited characteristics are more likely than other individuals of the same sex to obtain mates

an outgroup is:

a species or group of species from an evolutionary lineage that is closely related but not a part of the group of species we are studying (the ingroup)

what is an allopolyploid?

a species with multiple sets of chromosomes derived from different species

Cuvier believed that the strata represented....

a sudden catastrophic event that had destroyed many of the species living in that area

what are endospores?

a way in which prokaryotes withstand harsh conditions by developing these resistant cells when they lack water or essential nutrients

Gametes from two plant species combine and produce a haploid zygote, and that zygote develops into a haploid, hybrid plant. Why is the hybrid plant sterile? Select all that apply. a. The cells do not contain homologous chromosomes. b. Meiosis cannot occur. c. The plant cannot grow and reproduce asexually. d. The gametes produced cannot combine with the gametes of other plants. e. Mitosis cannot occur.

How could an asteroid impact kill off such a large number of different species all over the planet? Select all that apply. a. Debris from the impact orbiting around the Earth shielded sunlight, halting photosynthesis. b. Tsunamis, landslides, earthquakes, and heat caused by the impact killed organisms near the site of impact. c. The impact was so extreme that life at ground zero was vaporized.

abc

How could milk-drinking have provided strong favorable selection for lactase persistence? Select all that apply. a. Milk is protein and fat-rich and therefore could have been an important, high-quality food source. b. Milk was safer to drink than water and reduced exposure to pathogens. c. Milk may have been a critical food source during times of famine.

abc

Select the statements about the K-T boundary that are true. Select all that apply. a. The K-T boundary separates rock layers of the Cretaceous period from those of the Tertiary period. b. The K-T boundary dates to 65 million years ago (when the dinosaurs disappeared). c. The K-T boundary in Zumaia, Spain is sharp--representing an abrupt change in the marine ecosystem. d. The K-T boundary is a thin layer of clay found only in Gubbio, Italy.

abc

How do multiple lines of evidence (from the field, the fossil record, and molecular genetics) work together to illustrate stickleback evolution? Select all that apply. a. If the same morphological changes occur in the fossil record as in living populations, we might deduce that the genetic mechanism discovered in the living populations might be responsible for the changes observed in fossils. b. The fossil data show a pattern of evolution over long stretches of time. c. Genetic evidence reveals the precise molecular mechanism responsible for the change in pelvic structures in stickleback populations. d. Data obtained by analyzing living fish in lakes show the selective pressures present in different environments. e. We cannot draw any conclusions from recent data because evolution takes millions of years.

abcd

Which of the following are causes of evolutionary change? Select all that apply. a. mutation b. genetic drift c. gene flow d. natural selection

abcd

Darwin and Wallace independently arrived at the same conclusion that species change over time. Which observations supported their conclusions? Select all that apply. a. Tortoises from different Galapagos islands have distinct shells. b. Bird families clustered geographically: cockatoos in the Malay Archipelago and Australia, macaws and hummingbirds in the Americas. c. The fossilized remains of giant sloths were similar to the smaller, living sloths Darwin encountered. d. Birdwing butterflies were found throughout the Malay archipelago, but species differed slightly from island to island. e. The bony shells of armadillos resembled fossilized shells from the extinct Glyptodon. f. Mockingbirds from different Galapagos islands had subtle, consistent differences.

abcdef

Identify the four postulates of natural selection. Select all that apply. View Available Hint(s) a. Individuals in a population vary in the traits they possess. b. Some trait differences are heritable. c. Survival and reproductive success are variable among individuals in a population. d. All individuals in a population have equal reproductive success. e. Individuals with certain traits are more likely to survive and reproduce. f. Individuals in a population all possess the same traits.

abce

No two species of anoles lizards living in the same geographical location have dewlaps of the same size, shape or color. Why? Select all that apply. a. Differences in dewlaps keep different anole species reproductively isolated, even when they live together. b. Dewlap color is under strong selection. Dewlaps that contrast with a lizard's environment are more effective for communication. c. Male anole lizards use dewlaps to court females. d. An anole lizard will change its dewlap's appearance to effectively communicate in a given environment. e. Female anole lizards distinguish males of their own species from males of other species by their dewlaps.

abce

Darwin and Wallace made independent observations in different parts of the world. Which statements are true? Select all that apply. a. Both witnessed nature up close and realized it was a battlefield with massive casualties. b. Both collected huge numbers of specimens and realized that individuals vary within species. c. Wallace collected huge numbers of specimens and realized that individuals vary within species. Darwin's collections were destroyed by fire. d. Both observed slightly different species on nearby islands and concluded that species could change over time. e. Darwin observed slightly different species on nearby islands and concluded that species could change over time. The island species Wallace observed showed little variation.

abd

What does Dr. Carroll mean when he says, "while mutation is random, natural selection is not"? Select all that apply. a. Natural selection acts on traits. b. Natural selection favors some mutations. c. Mutations are caused by selective pressure dependent on environmental conditions. d. Mutations for advantageous traits are more likely to be passed on to the next generation.

abd

Which evidence is consistent with the asteroid impact hypothesis? Select all that apply. a. tektites, a type of melted rock b. shocked quartz in the K-T boundary layer c. plutonium 244 d. spherules, glass-like beads in the K-T boundary layer e. iridium

abde

How did Dr. Allison test his hypothesis that sickle cell disease was connected to malaria? Select all that apply. a. He expanded his study area beyond Kenya to the rest of East Africa to see if malaria and sickle disease were connected. b. He studied the way that the malaria parasite interacts with sickle cells. c. He evaluated blood samples for malaria parasites and the presence of sickle cells. d. He looked for the underlying genetic mechanism causing sickle cell disease.

In the lab, Nachman examined dark mice from two different populations living hundreds of miles apart. The mice looked nearly identical. Their dark color was caused by two different genes. What does this tell you? Select all that apply. a. Under very similar conditions, natural selection can favor very similar adaptations. b. Dark color evolved only once in rock pocket mice. c. Dark fur color evolved independently on each lava flow. d. Two completely different mutations in two separate genes can generate the same phenotype. e. There are at least two genes involved in creating dark mouse fur.

acde

Jonathan Losos and colleagues conducted experiments on small, hurricane-swept islands as "natural laboratories." Which of the following statements is true? Select all that apply. a. Natural selection can lead to rapid changes. The average leg length of lizard populations decreased within a few generations. b. Experiments on the small islands show evidence for adaptation by natural selection but not for evolution. c. Islands scrubbed by hurricanes allow researchers to introduce new lizard populations and observe their evolution.T d. he legs of the anoles placed on the islands became shorter, and their offspring inherited shorter legs. e. There are many small islands with similar environments, meaning that researchers can repeat their experiments and observations in several locations.

ace

The enzyme lactase breaks the sugar lactose into which compound(s)? Select all that apply. a. glucose b. sucrose c. fructose d. galactose

By consistently favoring some alleles over others, natural selection can cause ________, a process in which traits that enhance survival or reproduction tend to increase in frequency over time

adaptive evolution

In phylogenetic trees we cannot necessarily infer the _____ of the taxa or branch points shown in the tree

ages

_______ are another type of deep sea vent that releases water that has a high pH (9-11) and is warm (40-90 degrees C)

alkaline vents

What is a molecular clock?

an approach for measuring the absolute time of evolutionary change based on the observation that some genes and other regions of genomes appear to evolve at constant rates

symbiosis is...

an ecological relationship in which two species live in close contact with each other

heterochrony is

an evolutionary change in the rate or timing of developmental events

what is an autopolyploid

an individual that has more than two chromosome sets that are all derived from a single species

Some obligate anaerobes live exclusively by fermentation; others extract chemical energy by _____, in which substances other than O2, such as nitrate ions or sulfate ions, accept electrons at the "downhill" end of electron transport chains

anaerobic respiration

__________ features share similar function, but not common ancestry while _________ features share common ancestry but not necessarily similar function

analogous, homologous

a potential source of confusion in constructing a phylogeny is similarity between organisms that is due to convergent evolution - called _____ - rather than shared ancestry (homology)

analogy

In what eon was the oldest fossils of cells (eukaryotes) appear

archaean

A certain species of salamander was split into two populations by a wide, dry valley, and the populations began to diverge from each other. After a period of time, some members of the two populations began to interbreed in a hybrid zone at the southern end of the valley. Only weak reproductive barriers existed by this time, so the two populations could freely interbreed and re-establish gene flow. This outcome in a hybrid zone is known as __________. View Available Hint(s) a. punctuated equilibrium b. fusion c. reinforcement d. speciation e. stability

A farmer uses triazine herbicide to control pigweed in his field. For the first few years, the triazine works well and almost all the pigweed dies; however, after several years, the farmer sees more and more pigweed growing once again in the fields. Which of the following statements best explains the return of pigweed to the farmer's fields? a. Triazine-resistant pigweed has less-efficient photosynthetic pathways than the original form. b. Triazine-resistant weeds were more likely to survive and reproduce than were non-resistant individuals. c. Natural selection caused the pigweed to mutate, creating a new triazine-resistant species. d. The herbicide company started selling poor-quality triazine.

A particular antibiotic kills 99% of a bacterial population. What will be the result of the continued application of this antibiotic? a. Every time the antibiotic is given, it will kill 99% of the bacterial population. b. Over time, the antibiotic will become less effective at killing the bacteria. c. Eventually, all of the bacterial population will be wiped out. d. Over time, the antibiotic will cause mutations in the bacteria.

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? View Available Hint(s) a. Decreased fitness of the insects, allowing the birds to catch them more easily b. Increased fitness of large-beaked birds, leading to natural selection c. Increased fitness of the large-beaked birds, creating a new species d. Decreased fitness of small-beaked birds, creating a new species

A population of dark-eyed junco birds became established near the California coastline, many miles from the junco's normal habitat in the mixed-coniferous temperate forests in the mountains. Juncos have white outer tail feathers that the males display during aggressive interactions and during courtship displays. Males with more white in their tail are more likely to win aggressive interactions, and females prefer to mate with males with more white in their tails.Population sizes in the coastal areas have been reasonably large, and there are significant differences between the coastal and the mountain habitats. The coastal habitat is more open (making birds more visible) and has a lower junco density (decreasing intraspecific competition) than the mountain forests. Given this information, which of the following evolutionary mechanisms is the most likely cause of the difference between the coastal and mountain populations? a. gene flow b. natural selection c. mutation d. genetic drift

A swim bladder is a gas-filled sac that helps fish maintain buoyancy and evolved from the lungs of ancient fish. This evolutionary change is an example of which of the following processes? a. adaptive radiation b. exaptation c. paedomorphosis d. changes in Hox gene expression

According to the punctuated equilibria model, a. most evolution occurs in sympatric populations. b. most new species accumulate their unique features relatively rapidly as they come into existence, then change little for the rest of their duration as a species. c. given enough time, most existing species will branch gradually into new species. d. speciation is usually due to a single mutation.

Allele frequencies in a gene pool may shift randomly and by chance. What is this random shift called? a. directional selection b. genetic drift c. gene flow

An earthquake decimates a ground-squirrel population, killing 98% of the squirrels. The surviving population has broader stripes, on average, than the initial population. If broadness of stripes is genetically determined, which of the following processes most likely caused the change? a. directional selection b. a bottleneck effect c. disruptive selection d. a founder event

An ecological relationship between organisms of different species that are in direct contact can best be described as __________. View Available Hint(s) a. taxis b. symbiotic c. commensal d. mutualistic e. parasitic

Animals that possess homologous structures probably __________. View Available Hint(s) a. have increased genetic diversity b. evolved from the same ancestor c. had similar mutations in the past by chance d. are headed for extinction e. are not related

Antibiotic resistance in bacteria is an increasingly dangerous public health problem. Which of the following strategies would be most likely to reduce public health problems? a. eliminating use of all antibiotics b. increased funding for research into finding new antibiotics with new mechanisms of action c. wearing of breathing masks when outdoors d. eliminating use of methicillin

As Wallace traveled the Malay Archipelago, he noticed that western islands had placental mammals, like monkeys. Eastern islands had marsupial mammals, like kangaroos. How did Wallace explain this distribution? a. Monkeys and tree kangaroos compete against one another and cannot live together. b. The western islands were once connected to Asia and the eastern islands had been connected to Australia. The islands had never been connected to each other. c. God specially created monkeys on one set of islands and kangaroos on the other. d. Marsupial and placental mammals live in different habitats. Monkeys could only survive in the western islands and kangaroos in the eastern islands.

Bioremediation is __________. View Available Hint(s) a. the use of prokaryotes in producing pharmaceutical products b. the use of organisms to remove pollutants from the environment c. the use of prokaryotes in producing transgenic organisms d. the use of biological processes to remedy diseases e. the modification of prokaryotes for industrial purposes

Birds and mammals have four limbs. Which of the following statements describes this trait? a. the trait is an example of analogy rather than homology b. the trait is a shared ancestral character c. the trait is useful for distinguishing birds from mammals d. the trait is a shared derived character

Bony fish first evolved during the _____ . a. Mesozoic b. Paleozoic c. Cenozoic d. Precambrian e. Cretaceous

Consider a population of wildflowers in which the frequency of the red allele CR is p = 0.7. What is the frequency of the white allele (CW ) in this population? a. 0 b. 0.3 c. 0.49 d. 0.7

Continental drift (plate tectonics) has moved continents around the globe. Which of the following predictions would be most likely? a. Most species will occur only on one continent. b. The most recently separated continents will have the most closely related species. c. No species will occur on all continents. d. There is not enough information to make a prediction.

Does the ability of a Mycobacterium tuberculosis cell to infect a new host depend on its drug-resistant phenotype? View Available Hint(s) a. Yes, drug-resistant cells can infect a new host more easily than drug-susceptible cells. b. No, drug-susceptible cells and drug-resistant cells are equally likely to infect a new host. c. Yes, drug-susceptible cells can infect a new host more easily than drug-resistant cells.

Earth probably formed __________ years ago, and the first life evolved as early as __________ years ago. View Available Hint(s) a. 10 billion, 4.6 billion b. 4.6 billion, 3.9 billion c. 3.9 million, 2.0 billion d. 6,000, 6,000 e. Humans observed neither event, so there is no way to tell.

Evolution of shorter legs in anole lizards placed on small, hurricane-scrubbed islands is an example of which type of evolution? a. neither macroevolution nor microevolution b. microevolution c. macroevolution

Evolution works by __________. View Available Hint(s) a. converging on a particular phenotype b. "tinkering" with existing structures c. predicting the future d. constantly increasing complexity e. molding the environment to conform to the organisms living in it

For which of the following organisms would a phylogenetic tree constructed using sequence differences in mitochondrial DNA would be most valid for discerning their evolutionary relatedness? a. archaeans and bacteria b. chimpanzees and humans c. fungi and animals d. sharks and dolphins

Given what we know about evolutionary biology, which of the following places would be the most likely to have the highest number of species that are unique to the area (that is, that had evolved in that place). Assume that the conditions have existed for at least a few million years. a. a single mountain in the middle of a continent b. an isolated group of ocean islands c. a shallow estuary on a warm-water coast d. a grassland, with extreme climatic conditions, in the center of a large continent

How can an allopolyploid plant become a biologically fit new species? View Available Hint(s) a. Allopolyploid plants cannot become biologically fit new species; they are always sterile. b. Nondisjunction event during mitosis c. Synapsis of homologous chromosomes d. Nondisjunction event during meiosis

How do lactase supplements help people who are lactose intolerant? a. The supplements help replace the missing calcium and vitamins that people lack when they don't consume dairy products. b. The supplements provide the enzyme that breaks down the lactose in dairy products. c. The supplements create a nauseating feeling so that people are less likely to consume dairy products. d. The supplements bring about genetic changes that allow lactose intolerant people to produce lactase.

How many chromosomes would be found in an allopolyploid plant if its parents had diploid numbers of 2 and 10, respectively? View Available Hint(s) a. Diploid number of 6 b. Haploid number of 6 c. Haploid number of 12 d. Diploid number of 12

If biological species are defined in terms of reproductive compatibility, which of the following factors determines the formation of a new species? a. hybrid formation b. reproductive isolation c. gene flow d. gene pool expansion

If one organ is an exaptation of another organ, then which of the following statements is most accurate? a. The two organs occur in the same species. b. The two organs are homologous. c. The two organs are undergoing convergent evolution. d. The two organs have the same function.

In a Hardy-Weinberg population with two alleles A1 and A2 that are in equilibrium, the frequency of allele A2 is 0.1. What is the frequency of individuals with A1A1 genotype? a. 0.20 b. 0.81 c. 0.32 d. 0.42

In a species that has two chromosomes, suppose that a male has genotype aa for a gene on chromosome 1 and genotype bb for a gene on chromosome 2. If a female of this species has genotype AA for the gene on chromosome 1 and genotype BB for the gene on chromosome 2, which of the following represents the possible genotypes in a cell of their offspring? a. AB on chromosome 1, ab on chromosome 2 b. Aa on chromosome 1, Bb on chromosome 2 c. aB on chromosome 1, Ab on chromosome 2 d. AA on chromosome 1, bb on chromosome 2

In a very large population, a measurable trait has the distribution pattern shown in the diagram. Assume the trait is genetically determined. If there is no gene flow and the curve shifts to the left or to the right, which of the following processes is most likely occurring? a. disruptive selection b. directional selection c. genetic drift d. immigration or emigration

In the five-kingdom system, which kingdom consists primarily of unicellular eukaryotes? a. Fungi b. Protista c. Plantae d. Animalia e. Monera

In the oceans on either side of the Isthmus of Panama are 30 species of snapping shrimp, 15 species on the Pacific side and 15 different species on the Atlantic side. Species live at different water depths. Morphological and genetic data show that Atlantic and Pacific species that live at similar depths are sister species. Geological evidence indicates that the Isthmus of Panama started rising about 10 million years ago and the oceans were completely separated by the isthmus about 3 million years ago. Which of the following statements would best explain why the shallow-water sister species are more similar to each other than are the deeper-water species? a. The rise of the land bridge was accompanied by much volcanic activity. Volcanic ash contains heavy metals, which are known mutagens. Ash fall caused high levels of heavy metals in the ocean sediments underlying the deep water, resulting in accelerated mutation rates and faster divergence in deepwater shrimp. b. The shallow-water sister species have been geographically isolated from each other for a shorter time than the deep-water sister species have been. c. Cold temperatures, associated with deep water, have accelerated the mutation rate, resulting in faster divergence in deep-water shrimp. d. Fresh water entering the ocean from the canal is both less dense and cloudier than seawater. The cloudy fresh water interferes with the ability of shallow-water shrimp to locate mating partners, which reduces the frequency of mating, thereby slowing the introduction of genetic variation.

In the table, a Y indicates that the listed species possess trait 1, 2, or 3 and an N indicates that the listed species do not possess the trait. Given that phylogenies are based on shared derived characteristics, which of the following traits is useful in generating a phylogeny of species A, B, C, and D?Species ASpecies BSpecies CSpecies DTrait 1YYYYTrait 2YYNNTrait 3YNNN a. Trait 1 b. Trait 2 c. Trait 3 d. Traits 1, 2, and 3

In the western United States, pronghorn antelopes and domestic cattle often associate with one another in the same open rangeland. In a hypothetical situation, a certain species of flea originally fed only on pronghorn antelopes. Some of these fleas developed a strong preference for cattle blood and mated only with other fleas that also preferred cattle blood. The host mammal can be considered as the fleas' habitat. Which of the following processes most likely occurred if the situation persisted and a new species evolved? a. allopatric speciation and gametic isolation b. sympatric speciation and habitat isolation c. allopatric speciation and habitat isolation d. sympatric speciation and temporal isolation

Lactose intolerance in infants is more common in the population today than it was a hundred years ago. Why? a. Today there is a much higher percentage of adults who are lactose intolerant but still choose to have children. b. Today there are alternatives to breast milk, such as lactose-free formula and soy milk, so lactose intolerant infants can survive. c. Children today are not as healthy as children were a few hundred years ago. d. The large number of pollutants and toxins in the environment has led to more infants becoming lactose intolerant

Long necks make it easier for giraffes to reach leaves high on trees, while also making them better fighters in "neck wrestling" contests. In both cases, which kind of selection appears to have made giraffes the long-necked creatures they are today? View Available Hint(s) a. Stabilizing selection b. Directional selection c. Disruptive selection

Many present-day animal phyla appeared suddenly in fossils formed 535-525 million years ago, during the Paleozoic era of the Phanerozoic eon. This period is referred to as the Cambrian explosion. Does this period mark the beginning of animal life? a. Yes, animals first appeared during the Cambrian explosion in the Paleozoic era. b. No, animals originated about 700 million years ago during the Proterozoic eon. c. No, animals evolved nearly 1.2 billion years ago during the Proterozoic eon. d. This question cannot be answered from the information in the figure.

Mass extinctions create conditions that promote _____. a. gene flow b. adaptive radiation c. genetic drift d. microevolution e. paedomorphosis

Most people are lactose intolerant as adults, but nearly everyone produces sufficient lactase as an infant. However, in some cases, genetic mutations can occur that make an infant lactose intolerant. From an evolutionary perspective -- over thousands of years -- why would lactose intolerance in infants be very rare in the population? a. Lactose intolerance was such an embarrassing problem that many lactose intolerant parents chose not to have children, since the children might be lactose intolerant as well. b. Lactose intolerant infants could not digest breast milk and therefore usually died, never having the chance to pass the mutation on to their children. c. Lactose intolerant adults were not healthy enough to have children. d. Infants who were lactose intolerant were intolerant of all other foods as well.

No two people are genetically identical, except for identical twins. The main source of genetic variation among humans is a. environmental effects. b. the reshuffling of alleles in sexual reproduction. c. new mutations that occurred in the preceding generation. d. genetic drift

On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish prefer to breed only with males that have their same swimming ability. Which of the following phenomena have helped promote divergence between the mosquito populations? a. bottlenect effect and sexual selection b. sexual selection and natural selection c. bottlenect effect and founder effect d. increased gene flow and sexual selection

One out of 10,000 babies born in North America is affected by cystic fibrosis, a recessive condition. Assuming that the North American human population is in Hardy-Weinberg equilibrium for this trait, what percentage of the population is heterozygous for this trait? (Remember the equation for a population in Hardy-Weinberg equilibrium: p2 + 2pq + q2 = 1.) a. 0.01% b. 2% c. 1%

One possible outcome of hybridization is fusion of two species. Which of the following conditions is most likely to increase the probability of fusion of the two species as a result of hybridization? a. an increasing number of infertile hybrids is produced over the course of the next 100 generations b. an increasing number of viable, fertile hybrids is produced over the course of the next 100 generations c. no reproduction occurs in the hybrid zone d. a decreasing number of viable, fertile hybrids is produced over the course of the next 100 generations

Organisms that can cause nongonococcal urethritis are classified with _____. a. proteobacteria b. chlamydias c. spirochetes d. gram-positive bacteria e. cyanobacteria

Predict what will happen to the frequency of the sickle cell allele in areas where malaria has been eradicated. a. The sickle cell allele will increase in frequency. b. The sickle cell allele will decrease in frequency. c. The sickle cell allele frequency will not be affected.

Researchers studying a small milkweed population note that some plants produce a toxin and other plants do not. They identify the gene responsible for toxin production. One allele (T1) codes for an enzyme that makes the toxin, and another allele (T2) codes for a nonfunctional enzyme that cannot produce the toxin. Heterozygotes produce an intermediate amount of toxin. The allele frequency of T1 is determined to be 0.6 and the allele frequency of T2 is 0.4. What is the expected frequency of heterozygotes if the population is in Hardy-Weinberg equilibrium? a. 0.5 b. 0.48 c. 0.65 d. 0.25

Soapberry bugs use needlelike "beaks" to feed on seeds within the fruits of various plants. Bugs feed most successfully when their beak length matches the size of the fruit on which they are feeding. For 25 years, populations of soapberry bugs in central Florida have been feeding on small goldenrain tree fruits that were introduced to the area, rather than on the larger native balloon vine fruits that serve as food for other soapberry bug populations. Beak lengths of soapberry bugs are variable, but the average beak length is shorter in soapberry bug populations that feed on goldenrain tree fruits than in populations that feed on balloon vine fruits, as shown in the graph. How does natural selection act on beak length in soapberry bug populations? a. Natural selection decreases beak length in soapberry bug populations. b. The action of natural selection on beak length in soapberry bug populations varies with the environment. c. Natural selection increases beak length in soapberry bug populations.

Starting from the wild mustard Brassica oleracea, plant breeders have created the strains known as Brussels sprouts, broccoli, kale, and cabbage. Which of the following statements is correct with regard to the wild mustard? a. Natural selection is rare in wild populations of wild mustard. b. There is enough heritable variation in the wild mustard to permit these different varieties c. In wild mustard, most of the variation is due to differences in soil or other aspects of the environment. d. Heritable variation is low in wild mustard-otherwise this wild strain would have different characteristics.

Suppose conjugation occurs between an Hfr cell and an F- cell. Although not typical, what would have to occur for the recipient cell to become an Hfr cell? a. A portion of the F plasmid would have to be transferred to the recipient cell. b. The entire F factor would have to be incorporated into the recipient cell's chromosome. c. The entire F factor would have to be transferred to the recipient cell. d. A portion of the F factor would have to be incorporated into the recipient cell's chromosome.

although natural selection occurs through interactions between individual organisms and their environment. ________ do not evolve, rather, it is the _____ that evolves over time

individuals, population

The Dunkers are a religious group that moved from Germany to Pennsylvania in the mid-1700s. They do not marry with members outside their own immediate community. Today, the Dunkers are genetically unique and differ in allele frequencies at many loci from all other populations, including those in their original homeland. Which of the following mechanisms most likely explains the genetic uniqueness of this population? a. population bottleneck and Hardy-Weinberg equilibrium b. founder effect and genetic drift c. heterozygote advantage and stabilizing selection d. mutation and natural selection

The cow Bos primigenius (which is farmed for meat and milk) has a smaller brain and larger eyes than closely related species of wild ungulates. Which of the following statements best describes the process that led to differences between domesticated/farmed cows and their wild relatives? a. Natural selection resulted in changes in the lineage leading to domesticated cows because humans provided food for their cows. b. Artificial selection resulted in changes in the lineage leading to domesticated cows because humans wanted animals with high milk output and high muscle content. c. Natural selection resulted in changes in the wild species because humans preyed upon them. d. Artificial selection resulted in changes in the lineage leading to domesticated cows because humans wanted animals that would see predators and escape from them.

The lakes of northern Minnesota are home to many similar species of damselflies of the genus Enallagma. These species have apparently undergone speciation from ancestral stock since the last glacial retreat about 10 thousand years ago. Sequencing which of the following nucleic acids or proteins would probably be most useful in sorting out evolutionary relationships among these closely related species? a. conserved regions of nuclear DNA b. mitochondrial DNA c. ribosomal RNA d. amino acids in proteins

The scientific community was slow to accept the asteroid impact hypothesis. Why? a. Most global extinctions were thought to occur as a result of supernovas. b. At the time, most geologists thought that the Earth changed slowly and gradually, and not by major catastrophes. c. Dinosaur fossil evidence contradicted the hypothesis. d. Foraminifera appear on both sides of the K-T boundary.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data? a. Genes mutate faster in bats than in humans or whales. b. Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. c. Whales are not properly classified as mammals. d. Forelimb evolution was adaptive in people and bats, but not in whales.

There are a group of 13 related species of birds on a group of about 20 isolated oceanic islands. These species are grouped into four subgroups, with subgroup 1 evolving first (3 species), subgroup 2 evolving second (1 species), subgroup 3 evolving third (5 species), and subgroup 4 evolving last (6 species). If subgroup 4 evolved most recently, then which of the following statements is the most logical prediction? a. Subgroup 4 should be limited to the six islands that most recently emerged from the sea. b. The genomes of subgroup 4 should be more similar to each other than to the genomes of subgroup 3. c. The chances of hybridization between two subgroup 4 species should be less than the chances of hybridization between two subgroup 3 species. d. The species of subgroup 4 should share fewer anatomical homologies with each other than they share with the species of subgroup 4.

Three living species X, Y, and Z share a common ancestor T, as do extinct species U and V. A grouping that consists of species T, X, Y, and Z (but not U or V) makes up a. an ingroup, with species U as the outgroup. b. a paraphyletic group. c. a monophyletic taxon. d. a polyphyletic group.

Three populations of crickets look very similar, but the males have different courtship songs. If the cricket populations were to contact each other in the wild, the different courtship songs would most likely function as which type of reproductive isolating mechanism? a. gametic b. behavioral c. temporal d. postzygotic

True or false? A mating between a tetraploid individual and a diploid individual produces biologically fit offspring. View Available Hint(s) a. True b. False

True or false? Heterozygote advantage refers to the tendency for heterozygous individuals to have better fitness than homozygous individuals. This higher fitness results in less genetic variation in the population. View Available Hint(s) a. True b. False

True or false? The evolution of different ecomorphs on the Caribbean islands is an example of stabilizing selection. View Available Hint(s) a. True b. False

True or false? The last ice age produced many different species mainly because populations dispersed and colonized new habitats. View Available Hint(s) a. True b. False

Two juniper trees (Juniperus scopulorum and J. monosperma) have overlapping geographic ranges. Pollen grains (which contain sperm cells) from one species are unable to germinate and make pollen tubes on female ovules (which contain egg cells) of the other species. Which of the following isolating mechanisms keeps the two species separate? a. temporal isolation b. gametic isolation c. behavioral isolation d. habitat isolation

We are living during the _____era. a. Neogene b. Cenozoic c. Paleozoic d. Paleogene e. Mesozoic

What characteristics were used to classify organisms before Woese's tree of life analysis? View Available Hint(s) a. Composition of the cell wall b. Presence of a membrane-bound nucleus c. Number of cells in the organism d. Differences in ribosomal RNA sequences

What is the concern about using antibacterial and antimicrobial soaps? a. Antibacterial and antimicrobial products are far more toxic to bacteria than are antibiotics. b. The use of any chemical that kills bacteria can eventually lead to resistance to that chemical in the population of bacteria. c. Antibacterial and antimicrobial products are far more toxic to humans than are antibiotics. d. Doctors are concerned that people will stop using antibiotics, and start using more antibacterial and antimicrobial products instead.

What is the frequency of the A1A2 genotype in a population composed of 20 A1A1 individuals, 80 A1A2 individuals, and 100 A2A2 individuals? View Available Hint(s) a. 0.5 b. 0.4 c. 80 d. 0.1

What is the function of fimbriae? View Available Hint(s) a. they are used in motility b. they are used to attach the cell to its substrate or to other prokaryotes c. they are components of the outer cell wall in gram-negative bacteria d. they are used to transfer DNA during conjugation e. they protect the cell from dehydration

What role does nondisjunction play in the formation of a fertile allopolyploid hybrid? a. It causes the chromosomes to line up at the center of the cell during mitosis. b. It doubles the chromosome number in the hybrid c. It allows gametes of the two parent species to combine. d. It breaks down chromosomes that don't exist as homologous pairs.

What was the main selective pressure behind the evolution of different Anolis lizard species in the Caribbean? View Available Hint(s) a. Competitors b. Specific ecological niches c. Conspecifics d. Phylogeny

Which eukaryotic kingdom includes members that are the result of endosymbioses that included an ancient aerobic bacterium and an ancient cyanobacterium? a. Fungi b. Plantae c. Protista d. Animalia

Which group was not described in Woese's tree of life analysis? View Available Hint(s) a. Eukarya b. Prokarya c. Archaea d. Bacteria

Which listing of geological periods is in the correct order, from oldest to most recent? a. Cambrian, Permian, Devonian, Cretaceous b. Cambrian, Devonian, Permian, Cretaceous c. Devonian, Cambrian, Permian, Cretaceous d. Permian, Cambrian, Cretaceous, Devonian

Which molecule did Carl Woese study to produce his tree of life? View Available Hint(s) a. DNA b. Ribosomal RNA c. Messenger RNA d. Ribosome

Which of the following can promote allopatric speciation but not sympatric speciation? a. natural selection b. geographic isolation c. sexual selection d. polyploidy

Which of the following characteristics are demonstrated by the production of sterile mules after female horses mate with male donkeys? a. hybrid breakdown b. reduced hybrid fertility c. mechanical isolation d. reduced hybrid viability

Which of the following evolutionary processes or characteristics would most likely result in an archaean species whose rRNA is more similar to that of humans of mice? a. common ancestry b. convergent evolution c. homology d. retro-evolution by humans

Which of the following features permits a gene to act as a molecular clock? a. being acted upon by natural selection b. a reliable average rate of mutation c. a large number of base pairs d. a recent origin by a gene-duplication event

Which of the following is the best definition of evolution on the smallest scale? a. survival of the fittest b. change in allele frequencies in a population over time c. inheritance of acquired characters d. descent with modification

Which of the following is the first step in allopatric speciation? View Available Hint(s) a. genetic drift b. geographic isolation c. formation of a reproductive barrier d. hybridization e. polyploidy

Which of the following methods is most likely to lead to the production of two species from one ancestral species? a. sympatrically, by a point mutation affecting morphology or behavior b. allopatrically, after the ancestral species has split into two populations c. allopatrically, due to extensive inbreeding d. sympatrically, due to extensive inbreeding

Which of the following observations helped Darwin agree with Lyell that Earth was more than a few thousand years old? a. observing the variety of mockingbirds on the different Galapagos Islands as well as understanding that they were most similar to species in South America b. experiencing an earthquake and seeing fossils of ocean organisms high in the Andes c. observing the immigration of new finch species to a bare island in the Galapagos and seeing the development of a new species d. experiencing a tidal wave and seeing fossils of ocean organisms in the interior lands of the Galapagos islands

Which of the following pieces of evidence provides the best support for the claim that natural selection affected the evolution of ribozymes? a. Single-stranded RNA can have many shapes. b. Some strands of RNA replicate more often than others. c. Some strands of RNA are extremely chemically stable. d. Replication of RNA is flawless.

Which of the following statements provides the best evidence that the fossil record is 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.

Which of the following sets represents the most likely sequence of events in the origin of life? a. formation of protocells; synthesis of organic polymers; synthesis of organic monomers; formation of DNA-based genetic systems b. synthesis of organic monomers; synthesis of organic polymers; formation of protocells; formation of DNA-based genetic systems c. formation of protocells; synthesis of organic monomers; synthesis of organic polymers; formation of DNA-based genetic systems d. synthesis of organic monomers; synthesis of organic polymers; formation ofDNA-based genetic systems; formation of protocells

Which of the following situations leads to microevolution? a. Mutations in muscle cells are transferred to the next generation. b. Alleles move between populations that differ in allele frequencies. c. All individuals within a population have the same allele at a particular locus. d. An individual bird has a beak of a particular size that grows larger during a drought.

Which of the following statements about adaptive radiation is correct? View Available Hint(s) a. Adaptive radiation occurs very slowly over time. b. Adaptive radiation occurs within a single lineage. c. Adaptive radiation occurs in the presence of competitors. d. Adaptive radiation occurs in species that live in one habitat.

Which of the following statements about horizontal gene transfer is accurate? a. Horizontal gene transfer moves only genes that play a role in metabolism. b. Horizontal gene transfer is common in the evolution of life on Earth. c. Horizontal gene transfer among organisms does not occur today. d. Horizontal gene transfer occurs only among closely related organisms.

Which of the following statements about natural selection is true? View Available Hint(s) a. Natural selection can be used by farmers to generate organisms with desirable traits. b. Natural selection favors individuals that reproduce more than others. c. Natural selection occurs in opposition to evolution. d. Natural selection is a process whereby genes are selected randomly for preservation in the next generation.

Which of the following statements about obligate anaerobes is correct? View Available Hint(s) a. They live exclusively by cellular respiration or by anaerobic respiration. b. They are poisoned by O2. c. They will use O2 if it is present, but can obtain energy by fermentation if needed. d. They use O2 for cellular respiration and cannot grow without it. e. They obtain energy by oxidizing ferrous ions.

Which of the following statements about the evolution of Anolis lizards in the Caribbean islands is true? View Available Hint(s) a. Twig ecomorphs can jump very well. 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. The genetic relatedness of ecomorphs was determined by comparing their nuclear DNA sequences.

Which of the following statements best defines artificial selection? a. Artificial selection is a process that occurs when individuals inherit traits that enable them to survive and reproduce. b. Artificial selection is a process in which humans decide which plants and/or animals will and will not breed. c. Artificial selection is a process in which humans protect domesticated species from predation. d. Artificial selection is a process that produces beneficial mutations.

Which of the following statements best describes macroevolution? a. Macroevolution is defined as a change in allele or gene frequency over the course of many generations. b. Macroevolution is evolution above the species level c. .Macroevolution is the same as microevolution, but includes the origin of new species. d. Macroevolution is defined as the evolution of microscopic organisms into organisms that can be seen with the naked eye.

Which of the following statements best explains the existence of evolutionary trends, such as increasing body sizes among horse species? a. Evolution generally progresses toward some goal. b. In particular environments, similar adaptations can be beneficial to more than one species. c. Evolution tends toward increased complexity or increased size. d. A larger volume-to-surface area ratio is adaptive in many mammals.

Which of the following statements best represents a conclusion that Cuvier made when he considered the fossils found in the vicinity of Paris? a. Young rock strata contain only species that evolved recently. b. Multiple catastrophes caused extinctions and then species from other areas repopulated emptied areas. c. Multiple catastrophes caused extinctions and then new species evolved. d. Older rock strata contain species that are quite similar to current species because they evolved in that area.

Which of the following statements correctly describes a change that must occur for a new species to arise? a. The number of chromosomes in the gene pool must change. b. At least one gene, affecting one reproductive barrier, must change. c. Changes to centromere location or chromosome size must occur. d. Large numbers of genes that affect numerous phenotypic traits must change.

Which of the following statements describes a difference between the taxonomic levels of the hierarchical classification system? a. the relative genome sizes of the organisms assigned to each b. their inclusiveness c. morphological characters that are applicable to all organism d. show widely the organisms assigned to each are distributed throughout the environment

Which of the following statements is an accurate combination of postulates 1 and 2 of natural selection? View Available Hint(s) a. Drug resistance exists among all individuals in a population. b. Heritable variation exists for traits among individuals in a population. c. Heritable variation does not exist among individuals in a population. d. Environmental variation exists for traits among individuals in a population.

Which of the following statements is most accurate in comparing scientific theories and scientific hypotheses? a. Scientific theories are nearly the same things as scientific hypotheses. b. Scientific theories are supported by, and make sense of, many observations, whereas scientific hypotheses are narrow, testable ideas. c. Scientific theories cannot be tested because they relate to events that occurred only once, but scientific hypotheses can be tested because they relate to events that occur now. d. Scientific theories predict future events but scientific hypotheses describe past events.

Spiral-shaped bacteria are likely to be placed with _____. a. proteobacteria b. chlamydias c. spirochetes d. gram-positive bacteria e. cyanobacteria

Which of the following statements supports the hypothesis of "an RNA world" on early Earth? a. The oldest known fossils contain traces of RNA molecules. b. Some RNA molecules are important catalysts in modern cells. c. Single-stranded RNA molecules are linear and cannot form three-dimensional shapes.

Which of these conditions do NOT occur in populations evolving due to natural selection? a. Some inherited traits increase reproductive success. b. Individuals pass on most traits that they acquire during their lifetime. c. More offspring are produced than can survive. d. The populations vary in traits that can be inherited.

Which one of the following researchers developed a theory of evolution that was very similar to Charles Darwin's? View Available Hint(s) a. Cuvier b.Wallace c. Lyell d. Lamarck e. Hutton

Which pair of chickens should a farmer breed to produce larger chickens? View Available Hint(s) a. Large hen, small rooster b. Large hen, large rooster c. Small hen, large rooster d. Small hen, small rooster

Which process that can cause this is not the case? elimination of a trait convergent evolution inheritance of a trait appearance of adaptations within a group

Which term is used to describe populations that live close enough to interbreed? View Available Hint(s) a. Allopatry b. Sympatry c. Speciation d. Polyploidy

Which type of selection tends to increase genetic variation? View Available Hint(s) a. Directional selection b. Disruptive selection c. Stabilizing selection

Why are the large finches now living on the Galápagos Islands different from the original source population from a nearby island? View Available Hint(s) a. Genetic drift occurred in the two populations. b. All three answers are correct. c. The separation of habitats reduced gene flow between the populations. d. Natural selection favored individuals that were more fit in the new environment.

Why did Kingsley and his team cross marine and freshwater sticklebacks? a. To understand when in embryonic development the gene(s) for making a pelvis is/are active. b. To find the location of the gene(s) causing the difference between stickleback populations with and without spines. c. To compare the Pitx1 protein-coding sequence from fish with and without pelvises. d. To test whether Pitx1 was involved in the formation of pelvic spines.

Why did dark-colored rock pocket mice first appear in a population of light-colored rock pocket mice? a. There is dark lava rock in the area where they live. b. They have a genetic mutation that affects their fur color. c. Predators eat light-colored rock pocket mice. d. Individuals change color to blend in with the environment.

Why do dark-colored rock pocket mice on dark lava flows have white bellies? a. Mutations causing dark bellies do not occur. b. There is no selection for dark bellies by visual predators. c. White bellies are an important part of camouflage. d. There is a reproductive advantage to having a dark belly.

Why do researchers use rRNA in investigations of relationships between taxa that diverged hundreds of millions of years ago? View Available Hint(s) a. rRNA is traditionally the nucleic acid chosen for recent comparisons. b. DNA coding for rRNA changes relatively slowly. c. rRNA is never the nucleic acid chosen for comparisons. d. rRNA cannot mutate e. rRNA changes at different rates in different taxa.

Why is the enzyme lactase necessary to digest dairy products? a. Lactase converts monosaccharides like glucose into disaccharides like lactose. b. Lactase breaks down lactose into smaller molecules that can be absorbed by the cells that line the small intestine. c. Lactase converts the lipids in dairy products into carbohydrates, so that they can be used for energy and raw materials. d. Lactase converts monosaccharides like lactose into disaccharides like glucose.

_____ is rapid speciation under conditions in which there is little competition. a. Microevolution b. Adaptive radiation c. Paedomorphosis d. Gene flow e. Genetic drift

A lineage that diverges from all other members of its group early in the history of the group is called a _____

basal taxon

If a person has two normal copies of the hemoglobin allele, which statements are true? Select all that apply. a. The person is protected against malaria. b. The person is homozygous at the hemoglobin locus. c. The person is susceptible to malaria. d. The person is heterozygous at the hemoglobin locus.

What did researchers discover about the genetic mutation causing the loss of pelvic spines? Select all that apply. a. It results in a protein that is no longer functional. b. It occurred in a similar DNA region in freshwater stickleback populations all over the world. c. It is found in a regulatory region (a "switch") upstream of the coding region of the Pitx1 gene. d. It is found in the coding region of the Pitx1 gene.

What observations and evidence have Jonathan Losos and his colleagues gathered to support the theory of natural selection? Select all that apply. a. An anole lizard with a light-colored dewlap will develop a darker dewlap that stands out better in a bright environment. b. When Losos and colleagues transplanted tree-dwelling anoles to small, hurricane-scrubbed islands without trees, the lizards evolved to have shorter legs after only a few generations. c. DNA evidence suggests that the different lizard body types (twig, grass, etc.) evolved independently on each of the four large Caribbean islands. d. On each of the four large Caribbean islands, Losos observed the same distribution of anole lizard body types.

bcd

How prokaryotes reproduce

binary fission

Metabolic cooperation occurs between different prokaryotic species in surface-coating colonies called

biofilms

A fourth type of evidence for evolution comes from the field of _________, the scientific study of the geographic distribution of species

biogeography

what does the morphological species concept distiguish species by?

body shape and other structural features

mutualism

both organisms benefit

a severe drop in population size can cause the _________, by chance alone certain alleles may be overrepresented by survivors while others may be underrepresented, and some completely absent

bottleneck effect

The point at which two or more lineages diverge from their common ancestor is called a(n) ____________ or node.

branch point

each ____ represents the common ancestor of the two evolutionary lineages diverging from it

branch point

A fruit fly population has a gene with two alleles, A1A1 and A2A2. Tests show that 70%% of the gametes produced in the population contain the A1A1 allele. If the population is in Hardy-Weinberg equilibrium, what proportion of the flies carry both A1A1 and A2A2? a. 0.7 b. 0.49 c. 0.42 d. 0.21

A genetic change that caused a certain Hox gene to be expressed along the tip of a vertebrate limb bud instead of farther back helped make possible the evolution of the tetrapod limb. This type of change is illustrative of a. paedomorphosis. b. the influence of environment on development. c. a change in a developmental gene or in its regulation that altered the spatial organization of body parts. d. heterochrony.

A heritable trait is one that a. an organism acquires during its lifetime and passes on to its offspring. b. is dominant and hence is always inherited. c. is determined at least in part by genes passed from parents to offspring. d. is determined by genetic information encoded in proteins.

A paleontologist finds a new tyrannosaur in a site she is excavating, and wishes to date the fossil. What is the most likely method she will use? a. She will measure the amount of the radioisotope uranium-238 in the stratum where she found the tyrannosaur. b. She will determine the fossil's age by measuring the ratio of carbon-14 to carbon-12 in the fossil. c. She will infer the age of the fossil by dating layers of volcanic rock above and below the stratum containing the fossil.

Suppose 64% of the individuals in a remote mountain village can taste phenylthiocarbamide (PTC) and must, therefore, have at least one copy of the dominant PTC taster allele. If this population conforms to Hardy-Weinberg equilibrium for this gene, what percent of the population must be heterozygous for this trait? a. 16% b. 32% c. 48% d. 40%

A researcher has maintained a small population of fruit flies in the laboratory by transferring the flies to a new culture bottle after each generation. After several generations, the viability of the flies decreased greatly. Recognizing that small population size is likely to be linked to decreased viability, which of the following approaches would be the best way to reverse this trend of decreased viability? a. change the temperature at which the flies are reared b. transfer only the largest flies c. cross the flies with flies from another lab d. reduce the number of flies that are transferred at each generation

A rose bush is classified in domain _____ and kingdom _____. a. Eukarya ... Fungi b. Eukarya ... Protista c. Eukarya ... Plantae d. Eukarya ... Animalia e. Bacteria ... Archaea

A species of mouse that is preyed on by owls (which can see color) at dawn and dusk varies in coat color between dark and light brown. Under which of the following conditions will NO evolution occur if climate change results in the soil color becoming darker? a. Dark-colored mice are more likely to be eaten by owls. b. There is no way to make a prediction. c. There is no variability in the genes that control coat color. d. Light-colored mice produce more offspring than dark-colored mice.

A swim bladder is a gas-filled sac that helps fish maintain buoyancy. The evolution of the swim bladder from the airbreathing organ (a simple lung) of an ancestral fish is an example of a. paedomorphosis b. .adaptive radiation. c. exaptation. d. changes in Hox gene expression.

A team of scientists plans to study divergence of populations and needs to maximize the rate of divergence to see results within the period of their grant funding. They will form a new population by taking some individuals from a source population and isolating them so the source and new populations cannot interbreed. Which of the following strategies would maximize the likelihood of seeing divergence between the source and new populations in this study? a. choosing individuals from one extreme of the source population to form the new population and placing the new population in the same type of an environment as the source population b. choosing individuals with the most common phenotype in the source population to form the new population and placing the new population in a novel environment as compared to that of the source population c. choosing individuals from one extreme of the source population to form the new population and placing the new population in a novel environment d. choosing individuals with the most common phenotype in the source population to form the new population and placing the new population in the same type of an environment as the source population

A windstorm transports a few seeds of a plant species from Island A, where the species is abundant, to Island B, where prior to this event the plant species was not found. The environmental conditions on the two islands are very similar, but the islands are located far away from one another. Over time, a small population of this plant becomes established on Island B. A biologist samples plants on both islands and finds that allele frequencies on Island A differ substantially from allele frequencies on Island B at several genetic loci not known to affect survival or reproduction. Based on this information, the observed genetic changes mostly likely resulted from a. natural selection. b. mutation. c. genetic drift. d. gene flow (after the species became established on Island B).

According to the Hardy-Weinberg theorem, the frequencies of alleles in a population will remain constant if __________ is the only process acting on the gene pool. View Available Hint(s) a. mutation b. sexual selection c. random mating d. genetic drift e. immigration

According to the __________ model, morphological change occurs in spurts; species evolve relatively rapidly then remain unchanged for long periods. View Available Hint(s) a. gradual b. nondisjunction c. punctuated equilibrium d. geographic isolation

According to the theory of seafloor spreading, oceanic islands, such as the Hawaiian Islands, form as oceanic crustal plates move over a stationary "hot spot" in the mantle. Currently, the island of Hawaii (the youngest big island) is thought to be over a hot spot, which is why it is the only one of the seven large islands that has active volcanoes. Which of the following statements is also accurate with regard to the island of Hawaii? a. Hawaii should have a rich fossil record of terrestrial organisms. b. Scientists in search of ongoing speciation events are less likely to find them on Hawaii than on the other six large islands. c. Hawaii's species should be more closely related to those of nearer islands than to those of farther islands. d. Almost all of Hawaii's species do not occur anywhere else on Earth.

Adaptive radiations on archipelagos (island chains) represent some of the best-understood speciation events. Why is an ancestral species more likely to give rise to multiple descendent species on an archipelago than on an equal-sized area of mainland? a. Favorable mutations are more likely to arise on an archipelago as populations try to adapt to conditions on their specific island. b. By chance, different species will colonize different islands in a chain. c. Populations on nearby islands are more likely to be genetically isolated than populations that are equally close to one another on the mainland.

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

Animals first appeared during the _____. a. Mesozoic b. Paleozoic c. Precambrian d. Silurian e. Cenozoic

Bacteria that live around deep-sea, hot-water vents obtain energy by oxidizing inorganic hydrogen sulfide belched out by the vents. They use this energy to build organic molecules from carbon obtained from the carbon dioxide in seawater. These bacteria are __________. View Available Hint(s) a. photoheterotrophs b. chemoheterotrophs c. chemoautotrophs d. photoautotrophs

Suppose that a gene for coat color in mice has two alleles, B and b, where B is completely dominant and encodes a black coat color, and b is recessive and encodes a brown coat color. A mouse that is heterozygous has genotype _____, and its phenotype is _____. a. BB; black b. Bb; brown c. Bb; black d. bb; brown

Bagworm moth caterpillars feed on evergreens and carry a silken case or bag around with them in which they eventually pupate. Adult female bagworm moths are larval in appearance; they lack the wings and other structures of the adult male and instead retain the appearance of a caterpillar even though they are sexually mature and can lay eggs within the bag. Which of the following processes is exemplified by bagworm moths? a. sympatric speciation b. adaptive radiation c. paedomorphosis d. allometric growth

Black-bellied seedcrackers have either small beaks (better for eating soft seeds) or large beaks (better for hard seeds). There are no seeds of intermediate hardness; therefore, which kind of selection acts on beak size in seedcrackers? View Available Hint(s) a. Directional selection b. Stabilizing selection c. Disruptive selection

Charles Darwin __________. View Available Hint(s) a. eagerly published his theory before it was well-developed b. was the first person to conclude that organisms evolve c. proposed natural selection as the mechanism of evolution d. was the first to realize that fossils are remains of ancient organisms e. proposed unused parts of the body deteriorate

Compare sickle cell disease and malaria. a. Sickle cell disease and malaria are both inherited diseases. b. Sickle cell disease and malaria are both infectious diseases. c. Sickle cell disease and malaria are both potentially lethal diseases. c. Sickle cell disease and malaria are both genetic diseases.

Consider a wildflower population with the following allele and genotype frequencies. Frequency of the CR allele: p = 0.6 Frequency of the CW allele: q = 0.4 Frequency of CRCR : 50% Frequency of CRCW : 20% Frequency of CWCW : 30% Is this population in Hardy-Weinberg equilibrium? a. Yes, the genotype frequencies are what we would expect for a population in Hardy-Weinberg equilibrium. b. No, the frequency of genotype CWCW is too low. c. No, the frequency of genotype CRCW is too low. d. No, the frequency of genotype CRCR is too low.

Currently, two living elephant species (X and Y) are classified in the genus Loxodonta, and a third species (Z) is placed in the genus Elephas. Thus, which of the following statements would be accurate? a. Species X and Y are the result of artificial selection. b. Species X and Y are not related to species Z. c. Species X and Y share a greater number of homologies with each other than either does with species Z. d. Species X and Y share a common ancestor that is alive today.

Cystic fibrosis is a genetic disorder in humans where the person has two homozygous recessive alleles for the gene. If the disease is left untreated, it causes severe health problems in the individual. If 9 in 10,000 newborn babies have the disease, what are the expected frequencies of the dominant (A1) and recessive (A2) alleles according to the Hardy-Weinberg equation? a. f(A1) = 0.9800, f(A2) = 0.0200 b. f(A1) = 0.9604, f(A2) = 0.0392 c. f(A1) = 0.9700, f(A2) = 0.0300 d. f(A1) = 0.9997, f(A2) = 0.0003

Darwin used the phrase "descent with modification" to explain which of the following ideas? a. the unity of life b. descent of all organisms from a single, ancient ancestor c. both the unity and diversity of life d. the diversity of life

Dinosaurs went extinct during the _____. a. Devonian b. Precambrian c. Mesozoic d. Cenozoic e. Carboniferous

During the origin of the eukaryotic cell, it is thought that engulfed bacteria a. were always harmful to their hosts. b. had a mutually beneficial relationship with their hosts initially, but later evolved to become harmful to their hosts. c. did not initially have a mutually beneficial relationship with their hosts, but later evolved one d. always had a mutually beneficial relationship with their hosts.

Emerald ash borers are beetles whose larvae eat the leaves of ash trees. Without treatment of the trees, the beetles usually kill all ash trees in an area within 10 years. Which of the following events would provide the best possible avenue for saving the ash trees? a. constant application of DDT to kill the beetles b. development of a new pesticide that kills 50% of the emerald ash borers c. discovery of a gene in ash trees that prevents feeding by emerald ash borers and subsequent breeding of more ash trees with this chemical d. recognition by ash trees of the need for a chemical defense and subsequent production of the chemical by the ash trees to kill the beetles

Flowering plants first appeared during the _____. a. Devonian b. Precambrian c. Mesozoic d. Cenozoic e. Carboniferous

Fossils of Thrinaxodon, a species that lived during the Triassic period, have been found in both South Africa and Antarctica. Thrinaxodon had a reptile-like skeleton and laid eggs, but small depressions on the front of its skull suggest it had whiskers and, therefore, fur. Thrinaxodon may have been endothermic (able to generate its own internal heat). Which of the following statements is likely most accurate about Thrinaxodon? a. Antarctica and South Africa separated before Thrinaxodon evolved. b. The environment where Thrinaxodon lived was very warm. c. Mammals evolved from a relative of Thrinaxodon. d. Fossils found in a given area look like the modern species in that same area.

Generation-to-generation change in the allele frequencies in a population is _____. a. natural selection b. genetic drift c. microevolution d. macroevolution e. mutation

adaptations are...

inherited characteristics of organism that enhance their survival and reproduction in specific environments

House finches (birds) occurred 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. Which of the following terms best describes the process that had occurred if the two forms did not interbreed when their expanding ranges met? a. reinforcement b. sympatric speciation c. allopatric speciation d. prezygotic isolation

If organisms 1, 2, and 3 belong to the same class but to different orders and if organisms 3, 4, and 5 belong to the same order but to different families, which of the following pairs of organisms would be expected to show the greatest degree of morphological homology? a. 2 and 4 b. 2 and 3 c. 4 and 5 d. 1 and 4

If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would be most likely to happen in environments that lack antibiotics? a. These bacteria would try to make the cost worthwhile by locating and migrating to microenvironments where traces of antibiotics are present. b. These bacteria would maintain the antibiotic-resistance genes in case the antibiotics reappear. c. These bacteria would be outcompeted and replaced by bacteria that have lost the antibiotic resistance genes. d. These bacteria would increase the number of genes conveying antibiotic resistance.

In 1959, doctors began using the powerful antibiotic methicillin to treat infections of Staphylococcus aureus, but within two years, methicillin-resistant strains of S. aureus (MRSA) appeared. How did the resistant strains of S. aureus emerge? a. In response to treatment of Staphylococcus aureus infections with methicillin, bacterial populations gradually began to synthesize cell walls using a protein that was not affected by methicillin. b. In response to treatment of Staphylococcus aureus infections with methicillin, some bacteria began to synthesize cell walls using a protein that was not affected by methicillin. These bacteria survived the methicillin treatments and reproduced at higher rates than did other individuals. Over time, these resistant individuals became increasingly common. c. Staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other individuals. Over time, these resistant individuals became increasingly common.

In a hypothetical environment, fishes called pike-cichlids locate their prey by sight and eat small, immature algae-eating fish. Thus, the population of algae-eaters experiences predatory pressure from pike-cichlids. Which of the following possible changes is LEAST likely to occur in the algae-eater population in future generations? a. improved camouflage of the algae-eaters b. increased size of female algae-eaters that then produce more and larger young c. production of fewer offspring by algae-eaters d. decreased day-time activity by algae-eaters

In evolutionary terms, an organism's relative fitness is measured by its __________. View Available Hint(s) a. health b. stability in the face of environmental change c. contribution to the gene pool of the next generation d. genetic variability e. mutation rate

In some populations, 1 in 500 people have sickle cell disease. What reason does the film give for why a potentially deadly, inherited disease is found at such high frequencies? a. Individuals with two sickle cell alleles have an evolutionary advantage because they do not get sickle cell disease or get infected with malaria. b. Sickle cell alleles are new mutations and not enough time has gone by for these alleles to be eliminated from the population by natural selection. c. Individuals with one sickle cell allele are protected from malaria and do not have sickle cell disease, thus keeping the allele in the population. d. Individuals with two normal hemoglobin alleles get both sickle cell disease and are susceptible to malaria, so these alleles are eliminated from the population.

In the origin of the eukaryotes, endosymbiosis a. is thought to explain the origin of the nucleus. b. describes the engulfing of a photosynthetic bacterium that ultimately gave rise to mitochondria. c. most likely began with a heterotrophic endosymbiont entering the cell as undigested prey or as an internal parasite. d. most likely began with the endosymbiont entering the host cell through the endomembrane system.

In the video, what does the UK's Chief Medical Officer suggest for promoting the development of new antibiotics? a. conducting research to see whether our current antiviral medications could be used as antibiotics to combat bacteria b. spending federal tax money to set up government labs specifically for new drug research and development c. encouraging big pharmaceutical companies to start investing again in new drug research and development d. searching the rainforest for new chemicals that can be used as antibiotics

In this diagram, each fork represents which of the following ideas? a. groups of extinct organisms b. morphologic gaps in the fossil record c. the most recent common ancestor of the subsequent species d. groups of living organisms

It has been observed that organisms on many islands are different from, but closely related to, similar forms found on the nearest continent. Which of the following possible conclusions is best derived from this observation? a. Common environments are inhabited by the same organisms. b. The island forms and mainland forms are converging. c. Island forms are descended from mainland forms. d. Island forms and mainland forms have identical gene pools.

Large-scale, worldwide adaptive radiations have occurred in which of the following situations? a. whenever an evolutionary innovation was needed for organisms to thrive b. after colonization of an isolated island that contains suitable habitat and few competitor species c. after each of the big five mass extinctions d. when there are no available ecological niches

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. temporal isolation b. gametic isolation c. behavioral isolation d. habitat isolation

What is the frequency of the A1 allele in a population composed of 20 A1A1 individuals, 80 A1A2 individuals, and 100 A2A2 individuals? View Available Hint(s) a. The frequency of the A1 allele is 0.7. b. The frequency of the A1 allele is 0.5. c. The frequency of the A1 allele is 0.3. d. The frequency of the A1 allele is 0.1.

Many songbirds breed in North America in the spring and summer, and then migrate to Central and South America in the fall. They spend the winter in these warmer areas where they feed and prepare for the spring migration north and another breeding season. Two hypothetical species of sparrow, species X and species Y, overwinter together in mixed flocks in Costa Rica. In spring, species X goes to the east coast of North America, and species Y goes to the west coast. Which of the following factors most likely keeps these species separate? a. strong postzygotic isolating mechanisms in the winter b. strong prezygotic isolating mechanisms in the winter c. the two species reproduce in different geographic areas d. reinforcement of isolating mechanisms must be occurring in the spring

Members of two different species possess a similar-looking structure that they use in a similar way to perform about the same function. Which of the following observations would suggest that the relationship more likely represents homology than convergent evolution? a. The two species live at great distance from each other. b. The structures in adult members of both species are similar in size. c. The embryological development of the two structures are similar. d. Both species are well adapted to their particular environments.

Miller and Urey's experiments that attempted to recreate conditions on early Earth were significant because __________. View Available Hint(s) a.. they showed how polymers could form spontaneously on a clay substrate b. they showed how radiometric dating could be used to give the absolute ages of rocks and fossils c. they showed that organic molecules, such as amino acids, could be produced from inorganic molecules d. their findings upheld the endosymbiotic theory e. they produced the first protocells

Natural selection changes allele frequencies because some _______ survive and reproduce better than others. a. species b. alleles c. individuals d. loci

Of the following anatomical structures, which is most homologous to the bones in the wings of a bird? a. chitinous struts in the wings of a butterfly b. bones in the hind limbs of a kangaroo c. bones in the flippers of a whale d. bony rays in the tail fin of a flying fish

Over time, humans have steadily increased their movements across the continents of the Earth. Which of the following results has most likely been derived from these movements? a. increased genetic drift b. increased nonrandom mating c. increased gene flow d. increased geographic isolation

Pigs are vulnerable to infection by bird flu virus and human flu virus, both of which can be present in an individual pig at the same time. When both viruses infect a pig simultaneously, it is possible for genes from bird flu virus and human flu virus to be combined. If the human flu virus contributes a gene for Tamiflu resistance (Tamiflu is an antiviral drug) to the bird flu virus, and if this new virus is introduced to an environment lacking Tamiflu, then which of the following scenarios is most likely to occur? a. If the Tamiflu-resistance gene confers no benefit in the current environment, and has no cost, the virus will increase in frequency. b. The new virus will maintain its Tamiflu-resistance gene, in case of future exposure to Tamiflu. c. If the Tamiflu-resistance gene involves a cost, it will experience directional selection leading to reduction in its frequency. d. The Tamiflu-resistance gene will undergo mutations that convert it into a gene that has a useful function in this environment.

Plant species A has a diploid chromosome 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. 14. c. 28. d. 16.

Plant species X has a diploid number of 12. Plant species Y has a diploid number of 16. A new species, Z, arises as an allopolyploid from X and Y. The diploid number for species Z would probably be ________. a. 14 b. 56 c. 28 d. 16

Restriction enzymes in bacteria protect the bacteria from successful attack by bacteriophages, whose genomes can be degraded by the restriction enzymes. The bacterial genomes are not vulnerable to these restriction enzymes because bacterial DNA is methylated. This situation selects for bacteriophages whose genomes are also methylated. As new strains of resistant bacteriophages become more prevalent, they in turn select for bacteria whose genomes are not methylated and whose restriction enzymes instead degrade methylated DNA. Which of the following factors is most likely to cause the changes? a. neutral variation b. heterozygote advantage c. frequency-dependent selection d. evolutionary imbalance

Small Aristelliger lizards have difficulty defending territories, but large lizards are more likely to be preyed upon by owls. Which kind of selection acts on the adult body size of these lizards? View Available Hint(s) a. Disruptive selection b. Directional selection c. Stabilizing selection

Suppose that two distantly related species live in similar environments and share a distinctive characteristic that facilitates survival in their environment but is not found in their immediate ancestors. Based on this information, this distinctive feature most likely represents a. a homologous character. b. a character that arose by genetic drift. c. an analogous character. d. a character that spread from one species to the other by gene flow.

Sympatric speciation is __________. View Available Hint(s) a. the emergence of many species from a single ancestor b. the process by which most animal species have evolved c. the appearance of a new species in the same area as the parent population d. especially important in the evolution of island species e. initiated by the appearance of a geographic barrier

Systematists have used a wide variety of traits (characters) to reconstruct the phylogenies of particular groups of organisms. Which of the following types of characters are used to estimate a phylogeny? View Available Hint(s) a. morphological characters b. DNA sequence characters c. morphological characters and DNA sequence characters d. amino acid sequence characters e. behavioral characters

The Mesozoic era began approximately _____ million years ago. a. 4,600 b. 570 c. 251 d. 65 e. 25

The atmosphere of early Earth probably contained no O2 until the emergence of organisms that __________. View Available Hint(s) a. had chloroplasts b. were oxygen respiring c. used water as an electron source for photosynthesis d. were chemoautotrophic e. used hydrogen sulfide as an energy source

The effect of which Hardy-Weinberg condition is affected by population size? a. mutation b. gene flow c. genetic drift d. selection

The evolutionary effects of genetic drift are greatest when __________. View Available Hint(s) a. the population size is large b. intraspecific competition is weak c. the population size is small d. sexual selection occurs e. intraspecific competition is intense

The fruit fly Drosophila melanogaster has an allele that confers resistance to DDT and similar insecticides. Laboratory strains of D. melanogaster have been established from flies collected in the wild in the 1930s (before the widespread use of insecticides) and the 1960s (after 20 years of DDT use). Lab strains established in the 1930s have no alleles for DDT resistance. In lab strains established in the 1960s, the frequency of the DDT-resistance allele is 37%. Which statement is correct? a. Resistance to DDT evolved in some fruit flies in order to allow them to survive. b. Alleles for DDT resistance arose by mutation during the period of DDT use because of selection for pesticide resistance. c. The evolutionary fitness associated with the heritable trait of DDT resistance changed once DDT use became widespread.

The genome of an organism a. of one species is identical to the genome of an organism of a closely related species. b. only includes segments of the organism's DNA that do not encode proteins. c. includes all of the organism's DNA. d. only includes the organism's genes.

The oldest fossils usually __________. View Available Hint(s) a. have the longest half-lives b. contain more radioactive isotopes than younger fossils c. are found in the deepest strata d. are found in sediments formed during the Cenozoic era e. are found above younger fossils

The original source of all genetic variation is __________. a. sexual reproduction b. recombination c. mutation d. independent assortment e. natural selection

To apply parsimony to constructing a phylogenetic tree, a. choose the tree with the fewest branch points. b. choose the tree in which the branch points are based on as many shared derived characters as possible. c. choose the tree that represents the fewest evolutionary changes, in either DNADNA sequences or morphology. d. choose the tree that assumes all evolutionary changes are equally probable.

Two species of tree frogs that live sympatrically in the eastern 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. habitat differentiation b. difference in breeding seasons c. polyploidy d. female preference for male mating calls

What genotype frequencies are expected under Hardy-Weinberg equilibrium for a population with allele frequencies of p = 0.8 and q = 0.2 for a particular gene? View Available Hint(s) a. The expected genotype frequencies are 0.32, 0.64, and 0.04 for A1A1, A1A2 , and A2A2 , respectively. b. The expected genotype frequencies are 0.33, 0.33, and 0.33 for A1A1, A1A2 , and A2A2 , respectively. c. The expected genotype frequencies are 0.64, 0.32, and 0.04 for A1A1, A1A2 , and A2A2 , respectively. d. The expected genotype frequencies are 0.25, 0.5, and 0.25 for A1A1, A1A2 , and A2A2 , respectively.

What happened in the soapberry bug population in central Florida when the bugs began to feed on seeds from the goldenrain tree fruits which are much closer to the fruit surface? a. The length of each bug's beak gradually became shorter over time. b. Bugs developed short beaks, because they needed them to feed on the small fruits. c. Bugs with shorter beaks had more access to food, allowing them to produce more offspring.

What is genetic drift? View Available Hint(s) a. The physical splitting of a habitat b. The production of an evolutionarily independent group of organisms c. A change in allele frequencies caused by random events d. The motion of continental plates over time

What is lateral gene transfer? View Available Hint(s) a. Inheritance of a gene through mitosis b. Inheritance of a gene through meiosis c. Physical transfer of a gene from a species in one lineage to a species in another lineage. d. Inheritance of a gene from a parent

What is the difference between an F+ donor and an Hfr donor? a. The F+ donor has an F factor, but the Hfr donor does not. b. The Hfr donor has an F plasmid, but the F+ donor does not. c. The Hfr donor has an F factor integrated into its main chromosome, but the F+ donor does not. d. The Hfr donor has an F factor, but the F+ donor does not.

In a Hardy-Weinberg population with two alleles A1 and A2 that are in equilibrium, the frequency of allele A2 is 0.2. What is the frequency of individuals that are heterozygous for this allele? a. 0.02 b. 0.04 c. 0.16 d. 0.32

What is the most important characteristic of anole lizard species that keeps members of one species from mating with members of another species? a. Different species have differences in appearance, such as color or leg length. b. Different species eat different types of food. c. Different species living in the same habitat have different dewlaps. d. Different species live in different ecological niches.

What was the "oxygen revolution," which took place 2.3 billion years ago? a. The "oxygen revolution" was the rapid increase in atmospheric oxygen that took place 2.3 billion years ago, immediately preceding the origin of animals. b. The "oxygen revolution" was the rapid increase in atmospheric oxygen that took place 2.3 billion years ago, with the origin of plants. c. The "oxygen revolution" was the rapid increase in atmospheric oxygen that took place 2.3 billion years ago, dooming many prokaryotic groups.

When should a lactase supplement be taken in order to be most effective, and why? a. after the dairy product is consumed, since it takes a while for the lactase to start working b. taking it anytime is effective, because lactase works while in the bloodstream c. at the same time the dairy product is consumed, so that the lactase will be in contact with the lactose d. before the diary product is consumed, so the lactase has time to spread in the small intestine

Which discovery supports the hypothesis that evolution of the lactase-persistence trait was driven by the use of milk in pastoralist cultures? a. People who are lactase persistent have a mutation in the switch region of the lactase gene. b. The lactase gene is present in both humans and domesticated animals. c. Ancient pots used to hold milk are about the same age as the lactase-persistence mutations. d. Scientists have discovered different mutations for lactase persistence in different cultures.

Which of the following contributes the LEAST to the problem of antibiotic resistance? a. using high doses of antibiotics in animal feed, so that we are not exposed to the bacteria b. taking antibiotics for all infections, including viral infections c. taking the entire course of antibiotics as prescribed by the doctor d. stopping taking the antibiotics as soon as you feel better, thereby decreasing the exposure of the bacteria to the antibiotics

Which of the following factors contribute to limiting the capacity of organisms to overreproduce? a. inability of individuals to tolerate the physical conditions, production of many offspring per pair of parents, and abundance of food b. abundance of food, mortality from predators, and inability of individuals to tolerate the physical conditions c. inability of individuals to tolerate the physical conditions, lack of food, and mortality from predators d. lack of food, mortality from predators, and production of many offspring per pair of parents

Which of the following factors is most likely to produce a reproductive barrier in a single population? a. habitat sharing b. increased gene flow c. polyploidy d. decreased sexual selection

Which of the following factors most likely prevented adaptive radiation by mammals before the dinosaurs went extinct? a. nocturnal vision of the original mammals b. variation in teeth of the original mammals c. competition for food with the dinosaurs d. predation of dinosaur eggs by the original mammals

Which of the following ideas of Charles Darwin was most derived from his reading of Malthus's essay on human population growth? a. humans selected for specific traits in domesticated organisms b. variation among individuals in a population c. the ability of all species to over reproduce d. descent with modification

Which of the following is an observation or inference on which natural selection is based? a. Nearly all of each individual's offspring will survive and reproduce. b. Only well-adapted individuals produce offspring. c. Species produce more offspring than the environment can support. d. Individuals do not vary in their heritable characteristics.

Which of the following is found in eukaryotic cells but not in prokaryotic cells? a. plasma membrane b. DNA c. membrane-enclosed organelles d. cell wall

Which of the following molecules was most likely the first genetic material on Earth? 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 with catalytic activity d. oligopeptides located within protocells

Which of the following observations helped Darwin shape his concept of descent with modification? a. Species diversity declines farther from the equator. b. Birds live on islands located farther from the mainland than the birds' maximum nonstop flight distance. c. South American temperate plants are more similar to South American tropical plants than to European temperate ones. d. Fewer species live on islands than on the nearest continents.

Which of the following pairs is the best example of homologous structures? a. eyelessness in the Australian mole and eyelessness in the North American mole b. wings on an owl and wings on a hornet c. bones in the bat wing and bones in the human forelimb d. the shape of the dorsal fin in dolphins and the shape of the dorsal fin in sharks

______ are groups of organisms that share a unique common ancestor not shared by any other groups.

sister taxa

Which of the following results is the most likely outcome of increased gene flow between two populations? a. higher average fitness in both populations b. increased genetic difference between the two populations c. decreased genetic difference between the two population d. slower average fitness in both populations

Which of the following statements about autopolyploid individuals is true? View Available Hint(s) a. They can always produce fertile offspring. b. They can never produce viable offspring. c. They contain more than two haploid sets of chromosomes. d. They result from matings between individuals of different species.

Which of the following statements about evolutionary trees is accurate? a. Evolutionary trees cannot be tested by gathering more evidence. b. Evolutionary trees are considered evolutionary theories. c. Evolutionary trees are considered evolutionary hypotheses. d. Evolutionary trees are developed when they are confirmed by fossil evidence.

Which of the following statements about meiosis is correct? a. Meiosis in a diploid cell produces diploid daughter cells. b. Crossing over cannot occur during meiosis. c. Meiosis produces cells that differ genetically from the parent cell. d. In meiosis, each cell division produces two genetically identical daughter cells.

Which of the following statements best describes evolution? a. Individuals change in response to changes in the environment. b. The match between individuals and their environment decreases over time. c. Populations change genetically from one generation to the next. d. Natural selection favors the most abundant trait.

Which of the following statements best describes the difference between geographic isolation and habitat differentiation (isolation)? a. amount of genetic variation that occurs among two gene pools as speciation occurs b. identity of the kingdom or domain in which these phenomena occur c. relative location of two populations as speciation occurs d. speed (tempo) at which two populations undergo speciation

Which of the following statements best describes the effect of natural selection on a population? a. increased genetic variation among individuals in a population b. increased mutation rate in the population c. improved match between a population and its environment d. reduction in population size

Which of the following statements is accurate if we view evolution both as a pattern and a process? a. To study evolution as a pattern we study factors that cause changes in populations, while to study evolution as a process we draw on information from many other scientific fields. b. To study evolution as a pattern we rely on data from the past, while to study evolution as a process we study data from current day populations. c. To study evolution as a pattern we draw on information from many other scientific fields, while to study evolution as a process we study factors that cause changes in populations. d. To study evolution as a pattern we study data from current day populations, while to study evolution as a process we rely on data from the past.

Which of the following statements is accurate, at least according to our present knowledge? a. Prokaryotes acquired genes from eukaryotes many times; these genes can allow survival in extreme environments. b. Eukaryotes acquired nuclear genes only in the distant past; these genes can allow survival in anaerobic environments. c. Genes from prokaryotes have been acquired by some eukaryotes; these genes can allow survival in extreme environments. d. Prokaryotes acquired genes from fungi; these genes can allow the digestion of cellulose.

Which of the following statements most accurately applies to speciation? a. Speciation occurs only by the accumulation of small genetic changes over vast expanses of time. b. Speciation must begin with the geographic isolation of a small, frontier population. c. Speciation can involve changes to a single gene. d. Speciation occurs at such a slow pace that no one has ever observed the emergence of new species

Which of the following statements most accurately applies to volcanic oceanic islands shortly after the land has cooled enough to support life? a. There are major evolutionary innovations, which lead to rafting to nearby continents. b. There are mass extinctions, which lead to multiple bottleneck effects. c. There are a variety of empty ecological niches, which lead to adaptive radiation. d. There are adaptive radiations, which lead to multiple founder effects.

Which of the following taxa are problematic when the goal is to construct phylogenies that accurately reflect evolutionary history? a. polyphyletic taxa b. paraphyletic taxa c. polyphyletic taxa and paraphyletic taxa d. monophyletic taxa

Which of the following would be LEAST likely to appear in the fossil record? a. a marsh-dwelling species b. a burrowing species c. a desert-dwelling species d. a marine-dwelling species

Which of these are homologous structures? a. Plant root and plant leaf b. There are no homologous plant structures. c. Ivy leaf and pine needle

Which one of the following conditions would most likely cause allele frequencies to change by chance? a. mutation b. large population c. small populations d. gene flow

Which organisms are not examples of an adaptive radiation? View Available Hint(s) a. Anolis lizards of the Caribbean b. Honeycreeper songbirds of the Hawaiian islands c. Mammals and reptiles in the post-dinosaur age d. Horses and deer in the post-dinosaur age

In a Hardy-Weinberg population with two alleles A1 and A2 that are in equilibrium, the frequency of the allele A2 is 0.3. What is the frequency of individuals that are homozygous for this allele? a. 0.9 b. 9.0 c. 0.49 d. 0.09

Which statement about the beak size of finches on the island of Daphne Major during prolonged drought is accurate? a. Each bird evolved a deeper, stronger beak as the drought persisted. b. The frequency of the strong-beak alleles increased in each bird as the drought persisted. c. Each bird's survival was strongly influenced by the depth and strength of its beak as the drought persisted. d. Each bird that survived the drought produced only offspring with deeper, stronger beaks than seen in the previous generation.

Which statement correctly describes the role of chance in evolution? a. An allele that increases evolutionary fitness cannot be lost from a population by chance events. b. Evolution by natural selection proceeds by an accumulation of changes that occur by chance. c. The ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism's DNA.

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? a. dogs and wolves have very similar morphologies b. dogs and wolves belong to the same order c. dogs and wolves share a very recent common ancestor d. dogs and wolves are both members of the order Carnivora

Which term describes the ability of a trait to be passed on to offspring? View Available Hint(s) a. Adaptation b. Evolution c. Heritability d. Fitness

Why do some scientists believe that RNA, rather than DNA, was the first genetic material? View Available Hint(s) a. RNA can replicate more accurately than DNA. b. RNA contains uracil in place of thymine. c. RNA has both information storage and catalytic properties. d. All the protocells on early Earth contained RNA. e. RNA could have evolved into DNA.

Women often have complications during labor while giving birth to very large babies, whereas very small babies tend to be underdeveloped. Which kind of selection is most likely at work regarding the birth weight of babies? View Available Hint(s) a. Disruptive selection b. Directional selection c. Stabilizing selection

You read about soapberry bugs and select the correct statement describing relative fitness in these individuals. a. A soapberry bug with high relative fitness feeds more successfully on fruits than do other bugs. b. A soapberry bug with high relative fitness has more mates than other bugs. c. A soapberry bug with high relative fitness has a relatively high number of offspring that survive to reproductive age.

Many present day animal phyla appear suddenly in fossils formed 535-525 million years ago, early in the cambrian period, referred to as the _____

cambrian explosion

Oldest to youngest periods in the paleozoic

cambrian, ordovician, silurian, devonian, caboniferous, permian

how dramatic of a change is natural selection?

capable of substantial modification of species over many hundreds of generations

The cell wall of many prokaryotes is covered by a _____, a sticky layer of polysaccharides or protein

capsule

How does Dr. Allison's work provide an example of natural selection in humans? Select all that apply. a. In areas with malaria, natural selection causes individuals to acquire the sickle cell allele as protection against malaria. b. Natural selection caused the sickle cell allele to appear in east African populations. c. In areas with malaria, individuals with one sickle cell allele reproduced at higher rates than those with no sickle cell alleles. d. In areas without malaria, individuals with two sickle cell alleles reproduced at lower rates than those without sickle cell disease.

in what era did humans appear?

cenozoic

in what era did major radiation of pollinating insects happen

cenozoic

those that obtain energy from chemicals

chemotrophs

prokaryotes usually have ____ chromosomes while eukaryotes have linear chromosomes

circular

Using the methodology od cladistics, biologists attempt to place species into groups called _____, each of which includes an ancestral species and all of its descendants

clades

In the approach to systematics called _____, common ancestry is the primary criterion used to classify organisms

cladistics

how do prokaryotes have variation?

combination of rapid reproduction and mutation

What is intrasexual selection?

competition among individuals of one sex (often males) for mates of the opposite sex

What is disruptive selection?

conditions favor individuals at both extremes rather than those with intermediate phenotypes

What is directional selection?

conditions favor individuals exhibiting one extreme of a phenotype so it curve shifts left or right

what is a gene pool?

consists of all copies of every type of allele at every locus in all members of the population

Movements in the mantle cause the plates to move over time in a process called

continental drift

A biologist observes that a particular plant species is found in a forest but not in a nearby meadow. She hypothesizes that the plants could grow in the meadow but are not found there because their seeds have yet to land in the meadow. Which of the following would be the most appropriate way to scientifically evaluate this hypothesis? a. observing how long it takes the seeds to eventually reach the meadow b. measuring how far the seeds typically travel from their parent plant c. constructing a logical argument about why her hypothesis must be true d. scattering seeds in several areas of the meadow and observing whether they start to grow

A farmer wishes to develop a strain of high-yield corn that is also resistant to drought. He has the following individuals from the current year's crop: Individual A—Yield: 179 bushels/acre; drought resistance: high Individual B—Yield: 220 bushels/acre; drought resistance: low Individual C—Yield: 185 bushels/acre; drought resistance: medium Individual D—Yield: 140 bushels/acre; drought resistance: high Individual E—Yield: 200 bushels/acre; drought resistance: medium Which of the following crosses would produce the highest corn yield with the highest resistance to drought? View Available Hint(s) a. A and B b. B and B c. C and E d. A and E

A human is classified in domain _____ and kingdom _____. a. Eukarya ... Fungi b. Eukarya ... Protista c. Eukarya ... Plantae d. Eukarya ... Animalia e. Bacteria ... Archaea

A scientist samples a population of butterflies and finds that 56% are heterozygous at a particular locus. If the population is in Hardy-Weinberg equilibrium, what should be the frequency of the homozygous individuals in this population? a. 0.08 b. 0.70 c. 0.09 d. 0.44

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 itsoriginal habitat. Which of the following statements about these bird populations is true? View Available Hint(s) a. The birds were separated by a vicariance event. b. The populations were sympatric while they diverged. c. The populations will be able to interbreed even though they are different species. d. The populations will not be able to interbreed because they are different species.

After a drought in 1977, researchers hypothesized that on the Galapagos Island Daphne Major, medium ground finches with large, deep beaks survived better than those with smaller beaks because they could more easily crack and eat the tough Tribulus cistoides fruits. A tourist company sets up reliable feeding stations with a variety of bird seeds (different types and sizes) so that tourists can get a better look at the finches. Which of the following events is now most likely to occur to finch beaks on this island? a. no change in beak size and shape over time b. evolution of smaller, pointier beaks over time, until all birds have relatively small, pointy beaks c. evolution of yet larger, deeper beaks over time, until all birds have relatively large, deep beaks d. increased variation in beak size and shape over time

Almost all peppered moths in England were light colored before the Industrial Revolution. However, some dark forms were collected-the dark color is determined by a single, dominant allele of one gene. The bark of trees became darker during the Industrial Revolution in areas where heavy coal use in factories caused pollution. By about 1900, approximately 90% of the moths around industrial areas were dark, whereas light-colored moths were still abundant elsewhere. Apparently, birds could readily find the light moths against the dark trees in industrial areas and, therefore, were eating more light moths. Recently, use of cleaner fuels has resulted in tree bark becoming lighter again and the dark-colored moths have been disappearing. Which of the following statements best explains whether we should consider the forms different species? a. They are different species-as shown by the fact that natural selection has affected the frequency of the two forms. b. They are NOT different species-as shown by the fact that they live in the same habitats. c. They are different species-as shown by the fact that the two forms are reproductively isolated by habitat. d. They are NOT different species-as shown by the fact that they can interbreed.

Beetle pollinators of a particular plant are attracted to its flowers' bright orange color. The beetles not only pollinate the flowers, but they mate while inside the flowers. A mutant version of the plant with red flowers becomes more common with the passage of time. A particular variant of the beetle prefers the red flowers to the orange flowers. Over time, these two beetle variants diverge from each other to such an extent that interbreeding is no longer possible. Which of the following possible causes of speciation best describes the beetle example and what factor has driven it? a. sympatric speciation; allopolyploidy b. allopatric speciation; ecological isolation c. allopatric speciation; behavioral isolation d. sympatric speciation; habitat differentiation

Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been classified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification? a. The two forms live in similar habitats and have similar food requirements. b. The two forms have many genes in common. c. The two forms are very similar in appearance. d. The two forms interbreed often in nature, and their offspring survive and reproduce well.

Blue poppies native to China were grown at a plant-breeding center in California. The plants with the thickest leaves were most likely to survive and reproduce in the drier climate. After several generations, the percentage of thick-leaved plants had increased by 42%. This adaptation of the poppies to their new environment is due to __________. View Available Hint(s) a. neutral variation b. genetic drift c. disruptive selection d. directional selection e. stabilizing selection

In a comparison of birds and mammals, the condition of having four limbs is a. a shared derived character. b. an example of analogy rather than homology c. .a character useful for distinguishing birds from mammals. d. a shared ancestral character.

What is intersexual selection?

mate choice

Claytonia virginica is a plant with flowers that vary from white, to pale pink, to bright pink. Slugs prefer to eat pink-flowering over white-flowering plants (due to chemical differences between the two), and plants experiencing severe herbivory are more likely to die. The bees that pollinate this plant also prefer pink over white flowers, so that Claytonia with pink flowers produce more seeds than Claytonia with white flowers. A researcher observes that the percentage of different flower colors remains stable in the study population from year to year. Given no other information, if the researcher removes all slugs from the study population, what do you predict will most likely happen to the percentage of flower colors in the population over time? a. The distribution of flower colors will randomly fluctuate over time. b. The distribution of flower colors will not change. c. The percentage of white flowers will increase over time. d. The percentage of pink flowers will increase over time.

DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Instead, DDT is now largely ineffective against many insects. Which of the following possible actions would have had the best chance of preventing this evolution of DDT resistance? a. DDT application should have been continual. b. All habitats should have received applications of DDT at about the same time. c. The frequency of DDT application should have been higher. d. The use of DDT should have been interspersed with the use of other pesticides that have a different mode of action.

DNA evidence suggests that anole lizard species from the four largest Caribbean islands are related as shown in the figure. Which statement is true? a. Puerto Rico is the origin of all four anole lizard body types. b. Different body types evolved only once, and then groups of individuals with those body types ended up on different islands. c. The twig lizard on Puerto Rico evolved first and is the ancestor to all the other lizards. d. Different body types evolved repeatedly and independently on each island.

Dog breeders maintain the purity of breeds by keeping dogs of different breeds apart when they are fertile. This kind of isolation is most similar to which of the following reproductive isolating mechanisms? a. temporal isolation b. gametic isolation c. behavioral isolation d. habitat isolation

From his observations of organisms in the Galapagos Islands, Darwin reasoned that __________. View Available Hint(s) a. the shape of a bird's beak does not affect its ability to survive or reproduce b. all island species should be similar to each other c. the organisms in the Galapagos had been specially created to thrive in that environment d. organisms had adapted to new environments, giving rise to new species e. None of the listed answers are correct.

Genetic evidence supports which of the following explanations for the presence of 13 different finch species on the Galápagos islands? a. Many years ago, more than 13 different species of birds migrated to the islands. The current 13 finch species are the only species that survived. b. The 13 species have existed on the Galápagos islands since the islands first formed. c. Each of the 13 species migrated to the islands at different times over the years. d. Many years ago, a small population of a single finch species migrated to the islands and evolved into the current 13 species.

Hawaii is the youngest and most southeastern of the seven largest Hawaiian islands the oldest islands lie to the northwest. Kauai is the oldest and most northwestern big island. Hawaii is also closest to, and Kauai furthest from, the seafloor spreading center from which the Pacific plate originates, which lies about 5,600 km southeast of the island of Hawaii. Assuming equal rates of sedimentation from the islands onto the sea floor, which of the following places is the most likely location of the thickest sediment layer and thus the area with the greatest diversity of fossils above the oceanic crust? a. around the base of the island of Hawaii b. in the area where the islands are most concentrated (highest number of islands per unit surface area) c. between the island of Hawaii and the seafloor spreading center d. around the base of Kauai

How did some stickleback populations come to live exclusively in fresh water? a. The ancestors of freshwater sticklebacks are marine stickleback species that lived primarily in the ocean and migrated to freshwater to spawn. b. Sticklebacks developed traits that made them better adapted to fresh water and, as a result, they moved to a freshwater environment. c. Stickleback populations swam to freshwater lakes to spawn and stayed because there were no predators. d. Some stickleback populations became trapped in lakes that formed at the end of the last ice age.

How do foraminifera found in rock layers above the K-T boundary compare to those in rock layers below? a. Foraminifera above the boundary are larger and less diverse than those below. b. Foraminifera above the boundary are smaller and more diverse than those below. c. Foraminifera above the boundary are larger and more diverse than those below. d. Foraminifera above the boundary are smaller and less diverse than those below.

How does diploidy help to preserve genetic variation? See Concept 23.4 (Page) View Available Hint(s) a. It allows the frequency of a recessive allele in a population to be predicted under certain conditions. b. It fosters the exchange of genes between different populations. c. It restricts the gene pool by chance events such as floods or other catastrophic events. d. It allows recessive alleles that may not be favored in the current environment to be preserved in the gene pool by propagation in heterozygotes. e. It helps individual organisms make a greater contribution to the gene pool of the next generation.

Hybrid zones provide an opportunity to investigate __________. View Available Hint(s) a. polyploidy b. punctuated equilibrium c. mutations d. the evolution of reproductive isolation e. allopatric speciation

If the nucleotide variability of a locus equals 0%%, what is the gene variability and number of alleles at that locus? a. gene variability >0%>0%; number of alleles =2 b. =2gene variability =0%=0%; number of alleles =2 c. =2gene variability =0%=0%; number of alleles =0 d. =0gene variability =0%=0%; number of alleles =1=1

In 1949, Dr. Tony Allison observed a high frequency of Kenyans carrying the sickle cell allele in coastal areas and near Lake Victoria, but a lower frequency in the highlands. What did he hypothesize? a. He hypothesized that malaria causes sickle cell disease. b. He hypothesized that malaria is a genetic disease. c. He hypothesized that sickle cell disease was an environmental, not a genetic disease. d. He hypothesized that there was a connection between malaria and sickle cell disease.

prokaryote have _____ replication times

short

In peas, a gene controls flower color such that R1 = purple and R2 = white. The purple allele is dominant to the white allele. In an isolated pea patch, there are 36 purple-flowering plants and 64 white-flowering plants. Assuming Hardy-Weinberg equilibrium, what is the value of q for this population? a. 0.36 b. 0.64 c. 0.75 d. 0.80

In some jacana (a bird) species, males take care of the eggs and young, and females compete with each other for territories that contain one to several males. Female jacanas are significantly larger than males. Which of these statements is likely NOT an accurate description of this bird species? a. Variation in reproductive success should be greater in female jacanas than in males. b. Male jacana fitness is primarily limited by the ability to take care of eggs and raise young. c. Female jacana fitness is limited by the number of males in her territory with which she mates. d. Males and females have equal variation in reproductive success.

Mutations are always __________. a. neutral b. bad c. good d. a change in an individual's DNA

Over long periods of time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses? a. The ancestors of these organisms experienced harmful mutations that forced them to lose these structures. b. Natural selection accounts for these losses by the principle of use and disuse. c. Natural selection cannot account for losses, but can only account for new structures and functions. d. Under particular circumstances that persisted for long periods, natural selection reduced each of these structures because they presented greater costs than benefits.

Over time, bacteria have become increasingly resistant to antibiotics. Which of the following best explains this in terms of natural selection? a. Some bacteria began to tolerate the antibiotics, and passed this ability to their offspring. b. Antibiotics caused bacteria to reproduce more quickly than normal. c. Antibiotics caused mutations in the bacteria that were exposed to the largest doses of antibiotics. d. Bacteria that happen to have natural resistance to antibiotics survived and reproduced.

Recently, a museum scientist discovered a case of preserved grasshoppers that do not resemble any named species. No information about when and where the specimens were collected is available. Which of the following species concepts would be most appropriate to use in identifying and naming the new specimens? a. ecological b. genetic c. biological d. morphological

Scientists studying the origin of life have accomplished which of the following steps? a. formation of protocells that use DNA to direct the polymerization of amino acids b. formation of vesicles that use RNA as a template for DNA synthesis c. abiotic synthesis of protocells with self-replicating, catalytic RNA d. abiotic synthesis of RNA's bases (A, C, G, U)

Several dozen different proteins comprise the prokaryotic flagellum and its attachment to the prokaryotic cell, producing a highly complex structure. Certain proteins of the complex motor that drives bacterial flagella are modified versions of proteins that had previously belonged to plasma membrane pumps. This evidence best supports which of the following claims? a. The motors of bacterial flagella must have originated in other organisms. b. Bacteria that possess flagella must have lost the ability to pump certain chemicals across their plasma membranes. c. Natural selection produces organs that will be needed in future environments. d. Natural selection can favor new structures that have been coupled together from parts of other structures.

Some beetles and flies have antler-like structures on their heads, much like male deer. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of which of the following? a. homology b. similarity due to shared ancestry c. parsimony d. convergent evolution

Streptococcus pyogenes is classified with _____. a. proteobacteria b. chlamydias c. spirochetes d. gram-positive bacteria e. cyanobacteria

Suppose a BB female mouse mates with a Bb male mouse. Which of the following represents the probabilities of each genotype occurring among their offspring? a. 1/4 BB, 1/2 Bb, 1/4 bb b. 1/2 Bb, 1/2 bb c. 1/4 BB, 1/4 Bb, 1/2 bb d. 1/2 BB, 1/2 Bb

Suppose that a mutation for lactase-persistence occurred in each of the populations described below. In which populations would the mutation be more likely to increase in frequency over time because of natural selection? a. a population that raises potatoes and chickens b. a population that raises corn and beans c. a population that raises rice and tilapia fish d. a population that raises wheat and sheep

The Cenozoic era began approximately _____ million years ago. a. 4,600 b. 570 c. 245 d. 65 e. 25

The common edible frog of Europe is a hybrid between two named 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 rarely produce offspring. Which of the following statements is the best inference about the two Rana species? a. Prezygotic isolation exists between the two frog species. b. The hybrids form a separate species under the biological species concept. c. The two species are likely in the process of fusing back into one species. d. They are different species and postzygotic isolation exists between the two frog species.

When the individuals are members of different species, this movement of genes from one organism to the other is called

horizontal gene transfer

The following question is based on information from Kondo Y. and Kashiwagi A., Experimentally induced autotetraploidy and allotetraploidy in two Japanese pond frogs, Journal of Herpetology 38(3):381-92 (2004).Two researchers experimentally formed tetraploid frogs by fertilizing diploid eggs from Rana porosa brevipoda with diploid sperm from Rana nigromaculata. When they allowed the tetraploid frogs to mate 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 most likely result? a. The two parent species would interbreed and fuse into one species. b. The two parent species would recognize each other as mates. c. The tetraploids would invade the habitats of both parental species and cause them to go extinct. d. The tetraploids would be reproductively isolated from both parent species.

The number of cichlid species in Lake Victoria is declining, in part because of predation by Nile perch. Which of the following factors is also likely to contribute to the decline in the number of cichlid species in Lake Victoria? a. development of polyploidy b. reinforcement of isolating mechanisms c. stability of species d. fusion of species

The sequence of events illustrated in this figure results in a fertile hybrid plant called an allopolyploid. Which of the following statements is the most complete description of an allopolyploid? a. It contains more than two sets of chromosomes, which are derived from a single species. b. It is able to sexually reproduce with two or more other plant species because of its diverse set of chromosomes. c. It contains more than one pair of homologous chromosomes. d. It contains more than two sets of chromosomes, which are derived from two species.

The theory of evolution through natural selection is considered a scientific theory because __________. View Available Hint(s) a. it is general enough to provide many testable hypotheses b. it is supported by a massive body of evidence from many disciplines c. it is broad enough in scope to explain many observations d. All of the listed answers are correct. e. None of the listed answers are correct.

What does it mean that organisms have a nearly universal genetic code? a. The genes of nearly all organisms encode the same proteins. b. Nearly all organisms have the same genes. c. Nearly all organisms have the same mRNA. d. A specific DNA sequence encodes the same information in one species as it would in nearly any other.

What prevents speciation from occurring in sympatric populations? View Available Hint(s) a. Natural selection b. Genetic drift c. Geographical isolation d. Gene flow

When Charles Darwin set sail on the HMS Beagle, what did he and most of his contemporary scientists think about the origin of species? a. Most scientists thought species had been created in their current forms and were unchangeable, but Darwin believed in a natural origin of species. b. Most scientists, including Darwin, thought species were the product of natural processes and changed over time. c. Most scientists thought species were the product of natural processes, but Darwin had different ideas. d. Most scientists, including Darwin, thought each species was specially created by God in its present form and did not change over time.

When a species deviates from a 50:50 sex ratio (male to female), the members of the minority sex often receive a greater proportion of care and resources from parents than do the offspring of the majority sex. Which of the following processes most likely causes this pattern? a. sexual selection b. stabilizing selection c. balancing selection d. frequency-dependent selection

Which Anolis lizard ecomorph has long legs? View Available Hint(s) a. Twig b. Crown c. Trunk/crown d. Trunk/ground

Which characteristic was NOT advantageous for organisms in the million years after the catastrophic asteroid impact? a. swamp- or river-dwelling b. underground-dwelling c. self-contained spores d. large body size

Which of the following characteristics is most likely an adaptation? a. large seed size in wind-dispersed plants b. dark fur on mice that live in areas with light colored soil c. large size in St. Bernard dogs d. bright colors of prairie flowers

Which of the following comparisons illustrates differences in phenotypes caused by the environment? a. black versus palomino horse coat color b. average beak depth of birds before versus after drought c. coloration of monarch butterfly wings versus. viceroy butterfly wings d. bodies of "body builders" versus "couch potatoes"

Which of the following conditions is most likely to reinforce isolating mechanisms between two species that occasionally hybridize? a. the environment is changing b. prezygotic isolating mechanisms are in place c. gene flow is low d. hybrids have lower fitness than either parent population

Which of the following correctly describes what the video referred to as a "microbial cure"? a. Antibiotics are used to treat all infections, whether they are bacterial or viral, in order to bring about a full cure. b. Antibiotics are used only until the patient feels better, therefore reducing the exposure to the antibiotics. c. Antibiotics are used every time a patient has disease symptoms, in order to prevent an infection from occurring. d. Antibiotics are used to kill all of the infectious bacteria in a person.

Which of the following did all protocells have in common? a. the ability to synthesize enzymes b. the ability to replicate c. RNA genes d. a surrounding membrane or membrane-like structure

larger organism in a symbiotic relationship is known as the _____ and the smaller is known as the _____

host, symbiont

Which of the following factors would be the most likely to contribute to allopatric speciation? a. Selection pressures in the isolated population are similar to those in the ancestral population. b. Gene flow between the two populations is extensive. c. The separated population is large, and genetic drift occurs. d. Different mutations begin to distinguish the gene pools of the separated populations.

Which of the following factors would most likely cause an increase in population size of a prey animal? a. an increase in the number of predators b. a decrease in available food c. a reduction in camouflage d. an improvement in eyesight

Which of the following information would be most useful in creating a phylogenetic tree of a taxon? a. morphological data from fossil species b. a knowledge of color patterns in fossil and living species c. a knowledge of mutation rates in modern species d. morphological data from fossil and living species

Which of the following is an example of an adaptation in anole lizards? a. short tails in the anole lizards that live in grass and bushes b. small toe pads in the anole lizards that live in the tree canopy c. long leg length in the anole lizards that live mainly on twigs d. long legs in the anole lizards that live primarily on the ground and tree trunks

Which of the following organisms could be produced by artificial selection? View Available Hint(s) a. A dog that serves as the "eyes" for a blind individual. b. A rabbit that is housebroken. c. A chimpanzee that communicates through sign language. d. A cow that produces a large quantity of milk.

Which of the following organisms would be most likely to form a fossil? a. a rare squirrel b. a rare worm c. a common worm d. a common squirrel

Which of the following outcomes is most likely in hybrid zones where reinforcement of isolating mechanisms is occurring? a. increased gene flow between distinct gene pools b. formation of a stable hybrid zone c. a decrease in the genetic distinctness of two gene pools d. speciation

Which of the following possible causes of speciation is most likely to cause rapid speciation? a. natural selection b. colonization c. reinforcement d. polyploidy

Which of the following processes best describes the cause of a bottleneck effect? a. transfer of alleles in and out of a population due to movement of fertile individuals b. chance events that change allele frequency c. transfer of alleles to the next generation in proportions that differ from the current generation d. drastic decrease in the size of the population

Which of the following provides an example of a mechanical isolation as a prezygotic barrier? a. two species mate at different times b. two species live in different habitats c. two species share courtship activities d. two snails have shells that spiral in different directions

Which of the following statements about genetic variation is accurate? a. Genetic variation tends to be reduced when diploid organisms produce gametes. b. Genetic variation arises in response to changes in the environment. c. Genetic variation is created by the direct action of natural selection. d. Genetic variation must be present in a population before natural selection can act upon the population.

Which of the following statements about phylogenetic trees is true? View Available Hint(s) a. A monophyletic group consists of a common ancestor and some of its descendants. b. A paraphyletic group has not experienced lateral gene transfer. c. A paraphyletic group consists of an ancestral population and all of its descendants. d. A paraphyletic group consists of a common ancestor and some of its descendants.

Which of the following statements best describes Linnaeus' method of classifying organisms? a. Linnaeus grouped organisms into increasingly more complex categories. b. Linnaeus grouped organisms according to their geographical location. c. Linnaeus grouped organisms according to the linear hierarchy of the scala naturae. d. Linnaeus grouped organisms into increasingly more inclusive categories.

Which of the following statements best explains the need for the "2" in the 2pq term in the Hardy-Weinberg equation? a. The population is diploid. b. The population is doubling in number. c. Heterozygotes have two alleles. d. Heterozygotes can come about in two ways.

Which of the following statements is accurate about an organ described as vestigial? a. It must be analogous to some feature in an ancestor. b. It must be both homologous and analogous to some feature in an ancestor. c. It need be neither homologous nor analogous to some feature in an ancestor. d. It must be homologous to some feature in an ancestor.

Which of the following statements is accurate with regard to a phylogeny, as represented by a phylogenetic tree? a. Shared ancestral characters are excellent traits to use in developing a phylogeny. b. The ancestral group often has all the derived characters of the descendant species. c. A monophyletic group can be properly based on convergent features. d. Members of the same clade likely share many derived characters.

Which of the following statements is accurate with regard to the Cambrian explosion? a. The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record. b. Only the fossils of microorganisms occur 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 of the following statements is an accurate combination of postulates 3 and 4 of natural selection? View Available Hint(s) a. Individuals experience no success in their ability to survive or reproduce. b. Individuals experience uniform success in their ability to survive or reproduce. c. Individuals experience unlimited success in their ability to survive or reproduce. d. Individuals experience differential success in their ability to survive or reproduce due to differences in certain traits.

Which of the following statements is not a part of the Hardy-Weinberg principle? a. Even if allele A1 is dominant to allele A2 , it does not increase in frequency. b. When alleles are transmitted according to the rules of Mendelian inheritance, their frequencies do not change over time. c. If allele frequencies in a population are given by p and q, then genotype frequencies will be given by p 2, 2pq, and q 2 for generation after generation. d. The genotype frequencies in the offspring generation must add up to two.

Which of the following statements is the best definition of a hybrid zone? a. an area where members of two closely related species intermingle, but gene flow is prevented by prezygotic barriers b. an area where sterile hybrids form, kept separate by postzygotic barriers c. an area where the ranges of two closely related species overlap but do not interbreed d. an area where mating occurs between members of two closely related species, producing viable offspring

Which of the following taxonomic categories contains all the others listed here? View Available Hint(s) a. genus b. family c. species d. class e. order

Which of the various species concepts distinguishes two species based on the degree of genetic exchange between their gene pools? a. genetic b. ecological c. morphological d. biological

Which term describes a trait that increases an individual's ability to survive in a particular environment? a. Heritability b. Fitness c. Evolution d. Adaptation

Why do anatomical and molecular features often fit a similar nested pattern? a. Features of common ancestors are inherited without evolutionary changes, so such traits accumulate and are similar to each other. b. Different traits are layered during evolution. Therefore, the most ancient features become preserved in most groups of species. c. Similar features had arisen several times independently in evolutional history, which is why they fit a similar nested pattern. d. All life within a group shares some features with its ancestor and adds its own features, resulting in a nested pattern.

Why should we not view lactose intolerance as a disease in adult humans? a. The dietary supplement available for lactose intolerant adults causes more harm than good. b. The ability to produce the lactase enzyme is common in adult humans, but rare in infants. c. Humans do not normally produce the lactase enzyme at any time during their lives. d. Adult humans did not consume dairy products until fairly recently in our evolutionary history.

Within six months of effectively using methicillin to treat S. aureus infections in a community, all new S. aureus infections were caused by a resistant strain (MRSA). How can this best be explained? a. A patient must have become infected with MRSA from another community. b. In response to the drug, S. aureus began making drug-resistant versions of the protein targeted by the drug. c. S. aureus evolved to resist vaccines. d. Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency.

Why do some stickleback populations lack pelvic spines? Select all that apply. a. Freshwater fish have evolved different types of protective armor to keep them safe from predators. b. In freshwater, a marine stickleback sheds its spines. c. Pelvic spines are homologous to legs in four-legged animals and freshwater sticklebacks don't need hind limbs to move. d. In lakes with dragonfly larvae, pelvic spines can be disadvantageous, allowing the predatory larvae to grab the fish. e. In lakes where there are no large predatory fish, there is no advantage to having pelvic spines.

Phylogenetic trees are intended to show patterns of _____, not phenotypic similarity

descent

evolution is ....

descent with modification

what are protocells?

droplets with membranes that maintained an internal chemistry different from that of their surroundings

A group of small fish live in a lake with a uniformly light-brown sandy bottom. Most of the fish are light brown, but about 10 are mottled. This fish species is often prey for large birds that live on the shore. A construction company dumps a load of gravel in the bottom of the lake, giving it a mottled appearance. Which of these statements presents the most accurate prediction of what will happen to this fish population? View Available Hint(s) a. As the mottled fish are eaten, more will be produced to fill the gap. b. The ratios will not change. c. In two generations, all the fish will be mottled. d. There is no way to predict the result. e. The proportion of mottled fish will increase over time.

Bell and collaborators painstakingly documented a population of fossil sticklebacks from an ancient freshwater lake over a 20,000-year period. The prevalence of sticklebacks with full and reduced pelvises changed over time. Which is true? a. Initially (time A), fish with full pelvises dominated the lake population. b. The evolution of pelvic reduction seen in the fossil record is different from the phenomenon occurring in the lakes in Alaska today. c. In this population, having pelvic spines seemed to provide a selective advantage to stickleback fish. d. By the end of the studied period (time D) there was an approximately equal number of sticklebacks with and without spines. e. The population of fish with pelvic spines that arrived in the lake at time B evolved a reduced pelvis over time (beginning at time C).

By definition, a clade is __________. View Available Hint(s) a. parsimonious b. analogous c. polyphyletic d. paraphyletic e. monophyletic

Feathers either play a role, or may have played a role, in _____. a. gliding b. extended hops c. flight d. courtship e. all of these

this is a region in which members of different species meet and mate, producing atleast some offspring of mixed ancestry

hybrid zone

_____ are offspring that result from an interspecific mating

hybrids

Hox genes are thought to play an important role in the development of different morphologies because __________. View Available Hint(s) a. they affect the timing of reproductive development in the organism b. they affect the order of genes on certain chromosomes c. they affect the timing of development in the embryo d. they paved the way for the development of multicellular organisms e. they provide positional information in the embryo

In the five-kingdom system, prokaryotes are placed in the kingdom _____. a. Protista b. Animalia c. Fungi d. Plantae e. Monera

Molecular clocks are based on the idea that __________. View Available Hint(s) a. molecules resonate at a certain frequency that can be measured b. advantageous mutations arise at a constant rate c. mutations occur once every generation d. directional selection occurs at a constant rate e. on average, neutral mutations arise at a constant rate

Radiometric dating __________. View Available Hint(s) a. can be used to directly date fossils in sedimentary rock b. relies on the fact that the daughter isotope decays to the parent isotope at a constant rate c. only works on rocks younger than 75,000 years d. allows us to determine an absolute, errorless date e. allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata

The appearance of an evolutionary novelty promotes _____. a. mutation b. gene flow c. mass extinction d. paedomorphosis e. adaptive radiation

The first prokaryotic cells appeared during the _____. a. Jurassic b. Cretaceous c. Paleozoic d. Triassic e. Precambrian

The prokaryotic cells that built stromatolites are classified as _____. a. proteobacteria b. chlamydias c. spirochetes d. gram-positive bacteria e. cyanobacteria

The prokaryotic cells that were the first to add significant quantities of oxygen to Earth's atmosphere are classified as _____. a. proteobacteria b. chlamydias c. spirochetes d. gram-positive bacteria e. cyanobacteria

Varieties of Staphylococcus aureus that are resistant to the drug methicillin __________. View Available Hint(s) a. developed in response to the use of methicillin b. already existed in the population before methicillin was developed c. always have an advantage in every environment d. were strongly selected for as methicillin became widely used to treat bacterial infections e. The second and fourth answers are correct.

What situation most likely explains the occasional high frequency of certain inherited disorders among human populations established by a small population? See Concept 23.3 (Page) View Available Hint(s) a. nucleotide variability b. gene flow c. mutation d. bottleneck effect e. founder effect

Which of the following is an example of the pattern of evolution? View Available Hint(s) a. natural selection b. the inheritance of acquired characteristics c. heredity d. descent with modification e. the fossil record of the evolution of modern cetaceans

Which of the following observations led to Darwin's major inferences? View Available Hint(s) a. members of a population vary in their heritable traits b. body parts that are not used deteriorate over time c. organisms only go extinct when catastrophes occur d. although organisms can produce huge numbers of offspring, many of these offspring do not survive e. The first and fourth answers are correct.

Which of the following statements about endotoxins is correct? View Available Hint(s) a. Endotoxins are proteins secreted by prokaryotes. b. Endotoxins are components of the cell wall of gram-positive bacteria. c. The source of endotoxins is endospores. d. An example of a prokaryote that produces endotoxins is Clostridium botulinum. e. Endotoxins are released only when bacteria die and their cell walls break down.

Which of the following statements correctly describes how continental drift affects living organisms? View Available Hint(s) a. It may cause an increase or decrease in competition among different species. b. It happens so slowly that it does not affect current species. c. It causes changes in habitats, such as when large amounts of shallow marine habitat were lost in the formation of Pangaea. d. It causes climate change, which puts selective pressure on organisms. e. All but one of the listed answers are correct.

_____ are areas on the seafloor where heated water and minerals gush from Earth's interior into the ocean

hydrothermal vents

in a ______ environment, most prokaryotes lose water and shrink away from their wall (plasmolyze)

hypertonic

Which of these is an example of temporal isolation between two species? View Available Hint(s) a. the average weight of the individuals in one species is 45 kg, in the other species the average is 290 kg 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. one is a type of primate, the other is a type of marsupial e. one species is nocturnal, and the other species is not

the ___________________ defines a species in terms of its ecological niche, the sum of how members of the species interact with the nonliving and living parts of their environment

ecological species concept

Which observations led Darwin to establish a relationship between extinct and living animals? Select all that apply. a. Birdwing butterflies were found throughout the Malay archipelago, but species differed slightly from island to island. b. Mockingbirds from different Galapagos islands had subtle, consistent differences. c. Bird families clustered geographically: cockatoos in the Malay Archipelago and Australia, macaws and hummingbirds in the Americas. d. Tortoises from different Galapagos islands have distinct shells. e. The bony shells of armadillos resembled the shells of ancient Glyptodon fossils. f. The fossilized remains of giant sloths were found in places where smaller sloths now live.

eukaryotes originated by _____ when a prokaryotic cell engulfed a small cell that would evolve into an organelle found in all eukaryotes, a mitochondion

endosymbiosis

lipopolysaccharide components of the outer membrane of gram-negative bacteria

endotoxins

Darwin argued that classification should be based on ________ relationships

evolutionary

The horizontal line indicating a branch on a phylogenetic tree represents ancestral forms of the named taxon, thereby illustrating the ________ leading to that taxon.

evolutionary lineage

Biologists often represent the pattern of descent from common ancestors with a ______, a diagram that reflects evolutionary relationships among groups of organisms

evolutionary tree

proteins secreted by a certain bacteria and other organisms

exotoxins

__________ live in highly saline environments

extreme halophiles

_____ thrive in very hot environments

extreme thermophiles

these are archaea that live in environments so extreme that few other organism can survive their. They love extreme conditions that include extreme halophiles and extreme thermophiles

extremophiles

______ use O2 if it is present but can also carry out fermentation of anaerobic respiration in an anaerobic environment

facultative anaerobes

What is stabilizing selection?

favors intermediate variants and acts against extreme phenotypes

some prokaryotes stick to their substrate or to one another by means of hairlike appendages called _____

fimbriae

heterozygotes have heterozygote advantage because those who are heterozygous at a particular locus have greater _____ than homozygotes

fitness

endemic means it is...

found nowhere else in the world

When a few individuals become isolated from a larger population, this smaller group may establish a new population whose gene pool differs from the source population, called the ____

founder effect

What is balancing selection?

frequency dependent selection and heterozygote advantage

what happens in allopatric speciation?

gene flow is interrupted when a population is divided into geographically isolated subpopulations

smallest to largest in linnean system

genera -> family -> orders -> classes -> phyla -> kingdoms -> domains

chance events can cause allele frequencies to fluctuate unpredictably from one generation to the next, especially in small populations - a process called _____-

genetic drift

Use PCR to analyze the genes of prokaryotes collected from the environment via ___

genetic prospecting

natural selection can amplify or diminish only those ________ traits that differ among the individuals in a population

heritable

most cells in a filament carry out only photosynthesis, while a few specialized cells called _____ carry out only nitrogen fixation

heterocysts

organisms that require atleast one organic nutrient to make other organic compounds

heterotrophs

phenotypic and genetic similarities due to shared ancestry is called ____

homologies

What are orthologous genes?

homologous genes that are found in different species because of speciation

The underlying skeletons of the arms, forelegs, flippers, and wings of different mammals are ___________ that represent variations on a structural theme that was present in their common ancestor

homologous structures

Similarity resulting from common ancestry is known as

homology

What are paralogous genes?

homology results from gene duplication; hence, multiple copies of these genes have diverged from one another within a species

a _______ approach identifies the tree most likely to have produced a given set of DNA data, based on certain probability rules about how DNA sequences change over time

maximum lekelihood

according to the principle of ________ we should first investigate the simplest explanation that is consistent with the facts

maximum parsimony

In what era did dinosaurs evolve and radiate

mesozoic

In what era was the origin of mammals?

mesozoic

how was all of the prokaryotic genomes found from environmental samples using ___

metagenomics

Archaea that release methane as a by-product of their unique ways of obtaining energy-

methanogens

But in organisms that do not appear to be closely related, the bases that their otherwise very different sequences happen to share may simply be coincidental matches , called _____

molecular homoplasies

A taxon is equivalent to a clade only if it is ______ signifying that it consists of an ancestral species and all of its descendants

monophyletic

what are the three parts of the bacterial flagellum?

motor, hook, and filament

5. However, mistakes made during DNA replication sometimes result in ___________, changes to the nucleotide sequence of DNA.

mutations

What are the three main mechanisms that can cause allele frequency to change?

natural selection, genetic drift, and gene flow

_______ are differences in DNA sequence that do not confer a selective advantage or disadvantage

neutral variation

What two related but different ways is evolution viewed?

pattern and process

In eukaryotes that have cell walls , the walls are usually made of cellulose or chitin, but in prokaryotes that have cell walls, the walls usually contain ________ - a polymer composed of modified sugars cross-linked by short polypeptides

peptidoglycan

What are adaptive radiations?

periods of evolutionary change in which groups of organisms form many new species whose adaptations allow them to fill different ecological roles, or niches, in their communities

what is transduction?

phages carry prokaryotic genes from one host cell to another, mostly results from accidents that occur during the phage replicative cycle

what is the most recent eon?

phanerozoic

organisms that obtain energy from light are called

phototrophs

in an approach known as ______- we can predict that features shared by two groups of closely related organisms are present in their common ancestor and all of its descendants unless independent data indicate otherwise

phylogenetic bracketing

The evolutionary history of a group of organisms can be represented in a branching diagram called a _______

phylogenetic tree

Fimbriae are usually shorter and more numerous than ____ - appendages that pull two cells together prior to DNA transfer from one cell to the other

pili

3. When DNA replication is complete and the bacterium has reached twice its original size, the _________________ grows inward, dividing the parent cell into two daughter cells.

plasma membrane

in addition to its single chromosome, a typical prokaryotic cell may also have much smaller rings of independently replication DNA molecules called ____, most carrying only a few genes

plasmids

a species may originate from an accident during cell division that results in extra sets of chromosomes, a condition called ____

polyploidy

The ____ of evolution consists of the mechanisms that cause the observed pattern of change

process

in what eon did the oldest fossils of eukaryotic cells appear?

proterozoic

the term _____ is used to describe these periods of apparent stasis punctuated by sudden change

punctuated equilibria

radiometric dating is based on the decay of _____

radioactive isotopes

what three factors that give rise to high levels of genetic diversity in prokaryotes

rapid reproduction, mutation, and genetic recombination

RNA catalysts are called

ribozymes

This tree, like all the phylogenetic trees in this book, is _____, which means that a branch point within the tree )often drawn farthest to the left) represents the most recent common ancestor of all taxa in the tree

rooted

artificial selection is...

selecting and breeding individuals that possess desired traits

the ______ hypothesis supposes that mitochondria evolved before plastids through a sequence of endosymbiotic events

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