Clues from geology and paleontology suggest that simple cells, or their precursors, arose about _____ years ago.
A. 6 million
B. 4 billion
C. 2 billion
D. 1 million
E. 3 million
B. 4 billion
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Archaeons are not known to incorporate (fix) carbon dioxide.
Answer the following statement true (T) or false (F)
In contrast to regulators, animals that are conformers:
A. are able to alter their immediate external surroundings in order to maintain homeostasis. B. require large stores of ATP to maintain homeostasis. C. have a feature of their internal body composition that matches their external surroundings. D. cannot live in extremely cold environments, such as the Antarctic Ocean. E. cannot adapt to the external environment.
Which of the following is (are) true about predator–
prey coevolution? a. Each species exerts selection pressure on the other. b. Predators are selective agents that favor improved prey defenses. c. Prey with better defenses are selective agents that favor better predator hunting skills. d. All of the above are true. e. None of the above are true.
A diet rich in which vitamins may reduce the risk of free radicals that can cause health problems?
A. D and C B. D, C, and E C. C and B12 D. B12, C, and E E. C, E, and A