The earliest signs of life appeared on Earth during the ____ era
a. Archean
b. Paleozoic
c. Mesozoic
d. Cambrian
e. Cenozoic
ANSWER: a
Biology & Microbiology
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Members of the Archaea typically thrive in conditions of excessive
A. heat. B. acidity. C. alkalinity. D. salinity. E. All of the choices are correct.
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As an adult, which typical chordate embryonic traits do adult tunicates retain?
a. hollow, dorsal nerve cord b. notochord c. gill slits d. tail extending beyond anus e. carbohydrate “tunic”
Biology & Microbiology
Microbes of the same species that live together and cooperate in some way are
A. mutualistic. B. colonial. C. commensal. D. opportunistic.
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In cases of __________ growth, a population's growth rate remains constant and greater than zero.
Fill in the blank(s) with the appropriate word(s).
Biology & Microbiology