front 1 Which of the following factors weaken(s) the hypothesis of abiotic synthesis of organic monomers in early Earth’s atmosphere? | back 1 i. The relatively short time between intense meteor bombardment and the appearance of the first life-forms iii. Uncertainty about which gases comprised early Earth’s atmosphere |
front 2 2 How were conditions on the early Earth of more than 3 billion years ago different from those on today’s Earth? | back 2 a. Only early Earth was intensely bombarded by large space debris |
front 3 3 What is true of the amino acids that might have been delivered to Earth within carbonaceous chondrites | back 3 a. There were more kinds of amino acids on the chondrites than are found in living organisms today |
front 4 4 Which of the following is the correct sequence of events in the organ of life? | back 4 ii. Synthesis of organic monomers iii. Synthesis of organic polymers i. Formation of protobionts iv. Formation of DNA-based genetic systems |
front 5 5 Which of the following is a defining characteristic that all protobionts had in common? | back 5 a. A surrounding membrane or membrane-like structure |
front 6 6 The first genes on Earth were probably: | back 6 a. Auto-catalytic RNA molecules |
front 7 7 The synthesis of new DNA requires the prior existence of oligonucleotides to serve as primers. On earth, those primers are small RNA molecules. This latter observation is evidence in support of the hypothesized existence of | back 7 a. Earlier genetic systems than those based on DNA |
front 8 8 Several scientific laboratories across the globe are involved in research concerning the origin of life on Earth. Which of these questions is currently the most problematic and would have the greatest impact on our understanding if we were able to answer it? | back 8 a. How did RNA sequences come to carry the code for amino acid sequences? |
front 9 9 If natural selection in a particular environment favored genetic systems that permitted the production of daughter “cell” that were genetically dissimilar from mother “cells” then one should expect selection for which of the following? | back 9 ii. Polynucleotide polymerases without proofreading capability v. Polynucleotide polymerases with high mismatch error rates |
front 10 10 If the half-life of carbon-14 is about 5,730 years, then a fossil that has one-sixteenth the normal proportion of carbon-14 to carbon-12 should be about how many years old? | back 10 a. 22,900 |
front 11 11 Which measurement(s) would help determine absolute dates by radiometric means? | back 11 a. Two of the responses above are correct |
front 12 12 Approximately how far back in time does the fossil record extend? | back 12 a. 3.5 billion years |
front 13 13 What is true of the fossil record of mammalian origins? | back 13 a. It includes transitional forms with progressively specialized teeth |
front 14 14 If a fossil is encased in stratum of sedimentary rock without any strata of igneous rocks nearby then it should be: | back 14 a. Difficult to determine the absolute age of the fossil, because radiometric dating of sedimentary rock is less accurate than that of igneous rock |
front 15 15 An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to | back 15 a. Cause iron in ocean water and terrestrial rocks to rust |
front 16 16 Which of the following statements provides the strongest evidence that prokaryotes evolve before eukaryotes? | back 16 a. The oldest fossilized cells resemble prokaryotes |
front 17 17 What is true of the Cambrian explosion? | back 17 a. Recent evidence supports the contention that the Cambrian explosion may not have been as “explosive” as was once though |
front 18 18 What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth? | back 18 iv. Origin of cyanobacteria i. Origin of mitochondria iii. Origin of chloroplasts ii. Origin of multicellular eukaryotes v. Origin of fungal-plant symbioses |
front 19 19 If it were possible to conduct sophisticated microscopic and chemical analyses of microfossils found in 3.2 billion year old stromatolites, then one should be surprised to observe evidence of which of the following within such microfossils? | back 19 ii. A nuclear envelope iv. A nucleolus |
front 20 20 Recent evidence indicates that the first major diversification of multicellular eukaryotes may have coincided in time with the: | back 20 a. Melting that ended the “snowball Earth” period |
front 21 21 Which of these observations gives the most support to the endosymbiotic theory of the origin of eukaryotic cells? | back 21 a. The similarity in size between the cytosolic ribosomes of prokaryotes and the ribosomes within mitochondria and chloroplasts |
front 22 22 Which event is nearest in time to the end of the period known as snowball earth? | back 22 a. Cambrian explosion |
front 23 23 The snowball earth hypothesis provides a possible explanation for the: | back 23 a. Diversification of animals during the late Proterozoic era |
front 24 24 Which of the following characteristics should have been possessed by the first animals to colonize land? | back 24 i. Were probably herbivores iii. Had the ability to resist dehydration v. Were invertebrates |
front 25 25 The first terrestrial organism probably were considered which of the following? | back 25 ii. Photosynthetic iv. Prokaryotes |
front 26 26 If two continents converge and are united, then the collision should cause | back 26 a. A net loss of intertidal zone and costal habitat |
front 27 27 The major evolutionary episode corresponding most closely in time with the formation of Pangaea was the: | back 27 a. Permian extinctions |
front 28 28 One the basis of their morphologies, how might Linnaeus have classified the Hawaiian silverwords? | back 28 a. He would have placed them in more species than modern botanists do |
front 29 29 An organism has a relatively large number of Hox genes in its genome. Which of the following is true to this organism? | back 29 a. The organism has the genetic potential to have a relatively complex anatomy |
front 30 30 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 mature and can lay eggs within the bag. This is a good example of: | back 30 a. Paedomorphosis |
front 31 31 The loss of ventral spines by modern freshwater sticklebacks is due to natural selection operating on the phenotypic effects of Pitx1 gene: | back 31 a. Silencing (loss of expression) |
front 32 32 Larval flies (maggots) express the Ubx gene in all of their segments, and thereby lack appendages. If this same gene continued to be expressed throughout subsequent developmental stages, except in the head region, and if the result was a fit, sexually mature organisms that still strongly resembled a maggot, this would be an example of | back 32 a. Two of the responses above are correct |
front 33 33 How many of the following statements concerning the loss of hind limbs during whale evolution are true? | back 33 i. It is well documented by a series of transitional fossils ii. It explains why modern whales have vestigial pelvic girdles iii. It involved changes in the sequence or expression of hox genes iv. It is an example of macroevolution |
front 34 34 The existence of the phenomenon of exaptation is most closely associated with which of the following observation that natural selection cannot fashion perfect organism? | back 34 a. Evolution is limited by historical constraints |
front 35 35 One explanation for the evolution of insect wings suggest that wings began as lateral extensions of the body that were used as heat dissipaters for thermoregulation. When they had become sufficiently large, these extensions became useful for gliding through the air, and selection later refined them as flight-producing wings. If this hypothesis is correct, modern insect wings could best be described as: | back 35 a. Exaptation |
front 36 36 If one organ is an exaptation of another organ, then what must be true of these two organs? | back 36 a. They are both homologous organs |
front 37 37 Many species of snakes lay eggs. However, in the forests of northern Minnesota where growing seasons are short, only live-bearing snake species are present. This trend toward species that perform live birth in a particular environment is an example of | back 37 a. Species selection |
front 38 38 In the 5-7 million years that the hominid lineage has been diverging from its common ancestor with the great apes, dozens of hominid species have arisen, often with several species coexisting in time and space. As recently as 30,000 years ago, Homo sapiens coexisted with Homo neanderthalensis. Both species had large brains and advanced intellects. The fact that these traits were common to both species is most easily explained by which of the following? | back 38 a. Species selection |
front 39 39 The existence of evolutionary trends, such as increasing body sizes among horse species, is evidence that: | back 39 a. In particular environments, similar adaptations can be beneficial in more than one species |
front 40 40 Fossil evidence indicates that several kinds of flightless dinosaurs possessed feathers. If some of these father-bearing dinosaurs incubated clutches of eggs in carefully constructed nests, this might be evidence supporting the claim that: | back 40 a. Their feathers originally served as insulation, and only later became flight surfaces |
front 41 41 Several scientific laboratories across the globe are involved in research concerning the origin of life on earth. Which graph below, if the results were produced abiotically, would have the greatest promise for revealing important information about the origin of earth’s first genetic systems? | back 41 b |
front 42 47 If arrows indicate locations in the column where fossils of a particular type (see key above) first appear, then which core in Figure 25.2 has the most accurate arrangement of fossils? | back 42 Core A |
front 43 48 Which of the following reasons may explain why the sediment core lacks fossils of dragonflies with 3-feet wingspans? | back 43 i. This particular sediment core includes the correct stratum, but the part of the stratum captured by the core lacks such fossils. ii. The sea was not present at this site during the time that 3-feet dragonflies existed. iv. The sediments containing these fossils at this site may have been eroded away during a time when the sea had receded from this site. |
front 44 49 In order to properly interpret sediment cores, it is necessary to apply the principle of | back 44 a. Superposition |
front 45 50 Assuming the existence of fossilized markers for each of the following chemicals, what is the sequence in which they should be found in this sediment core, working from ancient sediments to recent sediments? | back 45 ii. chlorophyll iv. cellulose i. chitin coupled with protein iii. bone |
front 46 51 In order to assign absolute dates to fossils in this sediment core, it would be most helpful if | back 46 a. Volcanic ash layers were regularly interspersed between the sedimentary strata. |
front 47 70 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? | back 47 a. The evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules |
front 48 71 Which factor most likely caused animals and plants in India to differ greatly from species in nearby Southeast Asia? | back 48 a. India was a separate continent until 45 million years ago. |
front 49 72 Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception. | back 49 a. Genetic drift |
front 50 73 Which of the following steps has not yet been accomplished by scientists studying the origin of life? | back 50 a. formation of protocells that use DNA to direct the polymerization of amino acids |
front 51 74 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 | back 51 a. A change in a developmental gene or its regulation that altered the spatial organization of body parts. |
front 52 75 A swim bladder is a gas-filled sac that helps fish maintain buoyancy. The evolution of the swim bladder from lungs of an ancestral fish is an example of | back 52 a. Exaptation |
front 53 what year did darwin write about natural selection | back 53 1844 |
front 54 the four types of data that document the pattern of evolution | back 54 1) direct observations 2)homology 3)fossil record 4)biogeography |
front 55 3 requirements for national selction | back 55 1) individuals vary in their phenotypic traits 2) traits are heritable 3)variation in traits cause some individuals to experience higher fitness in a given environment |
front 56 what is life? | back 56 The phenomenon of life defies a short definition. We recognize and define life, or in other words, the living state of matter by what living things do and by the attributes of cells. |
front 57 · Four mechanisms cause allele frequency change | back 57 1. Genetic drift 2. Gene flow 3. Natural Selection 4. Mutation (variation in nucleotide sequence) |
front 58 The five conditions for non-evolving populations are rarely met in nature | back 58 1. No Mutations 2. Random Mating 3. No Natural Selection 4. Extremely Large Population Size 5. No Gene Flow |
front 59 · Three major factors alter allele frequencies and bring about most evolutionary change | back 59 1. Natural selection 2. Genetic drift 3. Gene flow |
front 60 genetic drift | back 60 describes how allele frequencies fluctuate unpredictably from one to generation to the next |
front 61 what is the founder effect | back 61 occurs when a few individuals become isolated from a larger population |
front 62 what is bottleneck effect | back 62 a sudden reduciton in population size due to a change in the enviroment |
front 63 effects of genetic drift | back 63 1. Genetic drift is significant in small populations 2. Can cause allele frequencies to change at random 3. Lead to a loss of genetic variation within populations 4. Can cause harmful alleles to become fixed |
front 64 gene flow | back 64 consists of the movements of alleles among populations |
front 65 directions selection | back 65 favors individuals at one extreme end of the phenotype range |
front 66 disruptive selection | back 66 favors individuals at both extremes of the phenotypic range |
front 67 stabilizing selection | back 67 intermediate variants and acts against extreme phenotypes |
front 68 sexual selection | back 68 natiural selection for mating success |
front 69 intrasexual selection | back 69 direct competition among individuals of one sex for mates of the opposite sex |
front 70 intersexual selection | back 70 occurs when individuals of one sex are choosy in selecting their mates |
front 71 heterozygote advantage | back 71 occurs when heterozygotes have a higher fitness that do both hmozygotes |
front 72 speciation | back 72 the origin of the new species |
front 73 microevolution | back 73 consist of changes in allele frequency in a population over time |
front 74 macroevolution | back 74 refers to broad patterns of evolutionary change above the species level, |
front 75 biological species concept | back 75 states that a species is a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring |
front 76 reproductive isolation | back 76 the existence of biological factors ( barriers) that impede two species from producing viable, fertile offspring |
front 77 hybrids | back 77 offspring of crosses between different species |
front 78 prezygotic barriers block fertilization from occurring by | back 78 o Impeding different species from attempting to mate o Preventing the successful completion of mating o Hindering fertilization if mating is successful |
front 79 · Postzygotic barriers prevent the hybrid zygote from developing into a viable, fertile adult | back 79 o Reduced hybrid viability o Reduced hybrid fertility o Hybrid breakdown |
front 80 morphological species concept | back 80 defines a species by structural features - applies to sexual and asexual species but relies on subjective criteria |
front 81 · The ecological species concept | back 81 views a species in terms of it ecological niche applies to sexual and asexual species and emphasizes the role disruptive selection |
front 82 · The phylogenetic species concept | back 82 defines a species as the smallest group of individuals on a phylogenetic tree It applies to sexual and asexual species, but it can be difficult to determine the degree of difference required for separate species |
front 83 Allopatric Speciation | back 83 gene flow is interrupted or reduced when a population is divided into geographically isolated subpopulations |
front 84 In sympatric speciation | back 84 speciation takes place in geographically overlapping populations |
front 85 polyploidy | back 85 extra set of chromosomes due to accidents during cell division |
front 86 autopolyploid | back 86 individual with more than two chromosome sets, derived from single species |
front 87 allopolyploid | back 87 species with multiple sets of chromosomes derived from different species |
front 88 sexual selection | back 88 can drive sympatric speciation |
front 89 · The Phanerozoic is divided into three eras: | back 89 the Paleozoic, Mesozoic, and Cenozoic |
front 90 The oldest known fossils | back 90 stromatolites |
front 91 when did oxygen begin accumulating in the atmosphere | back 91 2.7 billion years |
front 92 how old is the oldest fossil of eukaryptic cells date back to? | back 92 1.8 billion years |
front 93 · The endosymbiont theory | back 93 proposes that mitochondria and plastids (chloroplasts and related organelles) were formerly small prokaryotes living within larger host cells |
front 94 · Key evidence supporting an endosymbiotic origin of mitochondria and plastids | back 94 o Inner membranes are similar to plasma membranes of prokaryotes o Division and DNA structure is similar in these organelles and some prokaryotes o These organelles transcribe and translate their own DNA o Their ribosomes are more similar to prokaryotic than eukaryotic ribosomes o Chloroplasts are similar to certain cyanobacteria |