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Question
It is difficult to estimate when cyanobacteria appeared on Earth using evidence from the oxidation state of the Earth's crust, becauseA) several abiotic reactions could have formed Fe3+.
B) there are multiple forms of anoxygenic photosynthesis.
C) there are multiple groups of oxygenic photosynthetic bacteria.
D) several ancient anaerobic metabolisms form Fe3+.
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Which of the following statements about chlamydial infections is TRUE?
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In 2003, the majority of AIDS deaths occurred in
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Cholera is an example of a pandemic disease that
A) has multiple wild animal reservoirs and is thus difficult to eradicate.
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Influenza pandemics occur cyclically because
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An individual usually expresses ________ structurally distinct allele(s) that encode class I MHC proteins.
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