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Leto [7]
3 years ago
15

Earth's early atmosphere was primarily composed of

Biology
1 answer:
Paul [167]3 years ago
5 0

Answer:

The correct answer is ''carbon dioxide, water vapor and nitrogen.''

Explanation:

About 4.5 billion years ago, Earth was a very geologically active planet. So many volcanic fumes formed the primitive atmosphere, which was mostly made up of water vapor, carbon dioxide, sulfur, and nitrogen. At this point, oxygen was barely present and the oceans did not yet exist. The primitive atmosphere is the one before the Precambrian, it was reductive, that is, it lacked free oxygen, and only had ammonia, methane and hydrogen, the high temperature of the atmosphere in its early stages facilitated the reaction of these gases to form organic compounds from which life may have emerged. UV rays passed, because ozone did not exist.

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Answer:

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Thymine in DNA occurs as the result of thymidylate synthase creating _______, which then undergoes _______ to _______, then to _
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Answer:

Thymine in DNA occurs as the result of thymidylate synthase creating deoxythymidine monophosphate (dTMP), which then undergoes phosphorylation to deoxythymidine diphosphate (dTDP), then to Deoxythymidine triphosphate (dTTP), and incorporated into DNA by the DNA polymerase (DNA pol). Thymine in tRNA arises post-transcriptionally, by S-adenosylmethionine-dependent methylation of a uridine 5'-monophosphate (UMP) residue in RNA.

Explanation:

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Explanation:

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