Victory for the ACT Student Text 15e

340 • S CIENCE

11. Which of the following best describes the cause of the Cretaceous-Paleogene boundary extinction according to Scientist 2? A. A huge meteorite impact B. An abundance of iridium in Earth’s crust C. A massive release of volcanic gases Ǥ ϐŽ‘‘†…‘˜‡”‹‰ –Š”‡‡Ǧˆ‘—”–Š• ‘ˆ Earth’s surface 12. According to Scientist 1, a meteorite impact could cause a major extinction due to the resulting: F. shockwaves that limited photosynthesis. G. sunlight-blocking cloud of particles. H. unusually high concentration of the element iridium. J. release of toxic gases. 13. According to the information provided, evidence of a meteorite strike at the end of the Cretaceous period includes: A. high concentrations of iridium in sedimentary rock. B. major extinctions at other times in history. C. massive releases of gases, particularly carbon dioxide. Ǥ —Ž–‹’Ž‡ Žƒ›‡”• ‘ˆ •‘Ž‹†‹ϐ‹‡† „ƒ•ƒŽ– ‹ the Deccan Traps.

14. According to the information provided, both scientists agree that: F. volcanic activity occurred at the Cretaceous-Paleogene boundary. G. a meteorite hit Earth 65 million years ago. H. a meteorite was the cause of the Cretaceous-Paleogene boundary extinction. J. the Cretaceous-Paleogene boundary extinction is a greenhouse extinction ƒ••‘…‹ƒ–‡† ™‹–Š ϐŽ‘‘† „ƒ•ƒŽ–•Ǥ 15. According to Scientist 2, the Deccan Traps: A. led to a reduction in solar energy and photosynthesis. B. caused greenhouse warming. C. resulted from a series of volcanic eruptions. D. occurred roughly around the same time as the Permian-Triassic boundary extinction. 16. Both scientists would most likely agree that: F. there were multiple major extinctions throughout history. G. extinctions impact dinosaurs and other animal species but not plants. H. the Deccan Traps impacted the major extinction between the Cretaceous and Paleogene periods. J. a change in Earth’s atmosphere led to the extinction between the Cretaceous and Paleogene periods.