Scientists now believe that comets falling to early Earth played a role in the evolution of life. What role did these comets play?
A) They brought CO2 and H2O.
B) They brought ammonia ions (NH4).
C) They generated a lot of energy when they hit Earth.
D) All of the above are true.
D
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A friend asks you for a definition of endemic because she is writing a history paper and this word keeps occurring in the literature in reference to bison on the Great Plains of the United States. Your response is that the word endemic means
A. a species that has gone extinct since humans have evolved on Earth. B. a species that exists in many habitats on Earth. C. a species that has coevolved with humans on Earth. D. a species that lives in only one area of Earth.
Which of the following is controlled by the sensory-somatic nervous system?
a. heart b. lungs c. skeletal muscle d. endocrine glands
Vibrations are detected by
a. Pacinian corpuscles. b. Meissner's corpuscles. c. Merkel's discs. d. Ruffini endings. e. free nerve endings.
The use of lysozyme during the preparation of cheeses and wines is effective in reducing the numbers of
A. fungi. B. viruses. C. bacteria. D. prions. E. all microbes.