It is possible to make specific complementary dnas

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Unformatted text preview: substances directly into the bloodstream. 70 Exercise 13 pinnipeds, sea lions and walruses, are descended from 1. The author implies that which of the following was part of the long-standing view concerning pinnipeds? a terrestrial bearlike animal, whereas the remaining □ Pinnipeds are all descended from a terrestrial A Biologists have long maintained that two groups of bearlike animal. Line group, seals, shares an ancestor with weasels. But the 5 □ Pinnipeds share a common ancestor with turtles, B recent discovery of detailed similarities in the skeletal whales, and dugongs structure of the flippers in all three groups undermines □ Similarities among pinnipeds are due to their all C the attempt to explain away superficial resemblance as having had to adapt to aquatic life. due to convergent evolution—the independent development of similarities between unrelated groups in 10 2. The author implies which of the following about the response to similar environmental pressures. Flippers fact that turtles, whales, and dugongs all have flippers? may indeed be a necessary response to aquatic life, turtles, whales, and dugongs also have them. But the A ○ It can be explained by the hypothesis that turtles, co mmon detailed design found among the pinnipeds whales, and dugongs are very closely related. probably indicates a common ancestor. Moreover, 15 B ○ It can be explained by the idea of convergent walruses and seals drive themselves through the water evolution. C It suggests that turtles, whales, and dugongs ○ with thrusts of their hind flippers, but sea lions use their front flippers. If anatomical similarity in the evolved in separate parts of the world flippers resulted from similar environmental pressures, D ○ It undermines the view that turtles, whales, and dugongs are all descended from terrestrial ancestors. E ○ It is the primary difference between turtles, whales, as posited by the convergent-evolution theory, one 20 would expect walruses and seals, but not seals and sea lions, to have similar flippers. (162 words) and dugongs, on the one hand, and pinnipeds, on the other. 3. Select the sentence in the passage in which the author shows that the implication of the common view is contradicted by a new finding. 71 Question 4 is based on the following reading passage. 4. Which of the following, if true, would cast most According to astronomer S.A. Phinney, kicking a rock doubt on Phinney's estimate of the probability of hard enough to free it from Earth's gravity would require Earth rocks hitting Mars? a meteorite capable of making a crater more than 60 miles A ○ Rather than going in random directions, about across. Moreover, even if Earth rocks were freed by 25 percent of all particles ejected from Earth meteorite impact, Mars's orbit is much larger than Earth's, go in the same direction into space. B Approximately 100 meteorites large enough to ○ make a noticeable crater hit the Earth each year. C ○ No rocks of Earth origin have be...
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This document was uploaded on 09/16/2013.

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