Phase 1 of the creation of life on earth was _____________________. Phase 2 was the formation of self-replicating, information containing molecules. Phase 3 was the development of a membrane, enabling metabolism and creating the first cells.
a) the formation of RNA
b) the formation of small molecules containing carbon and hydrogen
c) the formation of DNA
d) the increase in the amount of atmospheric oxygen.
e) the formation of membranes so that later cells could develop
Ans: b) the formation of small molecules containing carbon and hydrogen
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If plants consume CO2 during photosynthesis, why hasn't all the atmospheric CO2 been used up? Select all that apply
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A thyroid disorder in which an excess of thyroid hormone is produced, causing anxiety, insomnia, heat intolerance,
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A certain species of land snail exists as either a cream color or a solid brown color. Intermediate individuals are relatively rare. Which of the following terms best describes this?
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