Bio Chapter 25 Questions

1) Which of the following factors weaken(s) the hypothesis of abiotic synthesis of organic monomers in early Earth's atmosphere? 1. the relatively short time between intense meteor bombardment and the appearance of the first life-forms 2. the lack of experimental evidence that organic monomers can form by abiotic synthesis 3. uncertainty about which gases comprised early Earth's atmosphere A) 1 only B) 2 only C) 1 and 2 D) 1 and 3 E) 2 and 3

2) How were conditions on the early Earth of more than 3 billion years ago different from those on today's Earth? A) Only early Earth was intensely bombarded by large space debris. B) Only early Earth had an oxidizing atmosphere. C) Less ultraviolet radiation penetrated early Earth's atmosphere. D) Early Earth's atmosphere had significant quantities of ozone.

12) Approximately how far back in time does the fossil record extend? A) 3.5 million years B) 5.0 million years C) 3.5 billion years D) 5.0 billion years

13) What is true of the fossil record of mammalian origins? A) It is a good example of punctuated equilibrium. B) It shows that mammals and birds evolved from the same kind of dinosaur. C) It includes transitional forms with progressively specialized teeth. D) It indicates that mammals and dinosaurs did not overlap in geologic time. E) It includes a series that shows the gradual change of scales into fur.

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

17) What is true of the Cambrian explosion? A) There are no fossils in geological strata that are older than the Cambrian explosion. B) Only the fossils of microorganisms are found in geological strata older than the Cambrian explosion. C) The Cambrian explosion is evidence for the instantaneous creation of life on Earth. D) The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record. E) Recent evidence supports the contention that the Cambrian explosion may not have been as "explosive" as was once thought.

16) Which of the following statements provides the strongest evidence that prokaryotes evolved before eukaryotes? A) Prokaryotic cells lack nuclei. B) The meteorites that have struck Earth contain fossils only of prokaryotes. C) Laboratory experiments have produced liposomes abiotically. D) Liposomes closely resemble prokaryotic cells. E) The oldest fossilized cells resemble prokaryotes

18) What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth? 1. origin of mitochondria 2. origin of multicellular eukaryotes 3. origin of chloroplasts 4. origin of cyanobacteria 5. origin of fungal-plant symbioses

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? I. double-stranded DNA II. a nuclear envelope III. a nucleoid IV. a nucleolus V. ribosomes A) II only B) III only C) II and IV D) II, III, and IV E) all five of these

24) Which of the following characteristics should have been possessed by the first animals to colonize land? 1. were probably herbivores (ate photosynthesizers) 2. had four appendages 3. had the ability to resist dehydration 4. had lobe-finned fishes as ancestors 5. were invertebrates A) 3 only B) 3 and 5 C) 1, 3, and 5 D) 2, 3, and 4 E) 1, 2, 3, and 4

21) Which of these observations gives the most support to the endosymbiotic theory for the origin of eukaryotic cells? A) the existence of structural and molecular differences between the plasma membranes of prokaryotes and the internal membranes of mitochondria and chloroplasts B) the similarity in size between the cytosolic ribosomes of prokaryotes and the ribosomes within mitochondria and chloroplasts C) the size disparity between most prokaryotic cells and most eukaryotic cells D) the observation that some eukaryotic cells lack mitochondria

25) The first terrestrial organisms probably were considered which of the following? 1. burrowers 2. photosynthetic 3. multicellular 4. prokaryotes 5. eukaryotes 6. plants and their associated fungi A) 2 and 4 B) 3 and 5 C) 1, 3, and 5 D) 2, 3, and 6 E) 2, 3, 5, and 6

26) If two continents converge and are united, then the collision should cause A) a net loss of intertidal zone and coastal habitat. B) the extinction of any species adapted to intertidal and coastal habitats. C) an overall decrease in the surface area located in the continental interior. D) a decrease in climatic extremes in the interior of the new supercontinent. E) the maintenance of the previously existing ocean currents and wind patterns.

27) The major evolutionary episode corresponding most closely in time with the formation of Pangaea was the A) Cambrian explosion. B) Permian extinctions. C) Pleistocene ice ages. D) Cretaceous extinctions.

31) The loss of ventral spines by modern freshwater sticklebacks is due to natural selection operating on the phenotypic effects of Pitx1 gene A) duplication (gain in number). B) elimination (loss). C) mutation (change). D) silencing (loss of expression).

35) One explanation for the evolution of insect wings suggests 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 A) adaptations. B) mutations. C) exaptations. D) isolating mechanisms. E) examples of natural selection's predictive ability.

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 A) natural selection. B) sexual selection. C) species selection. D) goal direction in evolution. E) directed selection.

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? A) species selection B) uniformitarianism C) sexual selection D) convergent evolution

39) The existence of evolutionary trends, such as increasing body sizes among horse species, is evidence that A) a larger volume-to-surface area ratio is beneficial to all mammals. B) an unseen guiding force is at work. C) evolution always tends toward increased complexity or increased size. D) in particular environments, similar adaptations can be beneficial in more than one species. E) evolution generally progresses toward some predetermined goal.

40) Fossil evidence indicates that several kinds of flightless dinosaurs possessed feathers. If some of these feather-bearing dinosaurs incubated clutches of eggs in carefully constructed nests, this might be evidence supporting the claim that A) dinosaurs were as fully endothermal (warm-blooded) as modern birds and mammals. B) their feathers originally served as insulation, and only later became flight surfaces. C) the earliest reptiles could fly, and the feathers of flightless dinosaurs were vestigial flight surfaces. D) the feathers were plucked from the bodies of other adults to provide nest-building materials. E) all fossils with feathers are actually some kind of bird.

72) Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception. A) vacant ecological niches B) genetic drift C) colonization of an isolated region that contains suitable habitat and few competitor species D) evolutionary innovation E) an adaptive radiation in a group of organisms (such as plants) that another group uses as food

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 A) an evolutionary trend. B) exaptation. C) changes in Hox gene expression. D) paedomorphosis. E) adaptive radiation.