Which Statement About the Atmosphere and Life on Earth Is

question 52

Multiple Choice

Which statement about the atmosphere and life on Earth is correct?

• A)Life on Earth arose once oxygen was present.
• B)Life on Earth arose once temperatures of gases warmed.
• C)Life on Earth arose before oxygen was present.
• D)Life on Earth arose once the products of photosynthesis such as oxygen were present.

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Definitions:

D-Arabinose

A naturally occurring aldopentose sugar, notable for its role in the biosynthesis of many plant and bacterial polysaccharides.

Kiliani-Fischer Synthesis

A chemical reaction procedure used for the synthesis of monosaccharides by elongating the carbon chain of an aldose and subsequently introducing a new stereocenter, enabling the derivation of higher sugars from simpler ones.

Tollen's Test

A chemical reaction used to detect aldehydes, where a positive result leads to the formation of a silver mirror on the reaction vessel.

Methyl Iodide

Methyl iodide, also known as iodomethane, is a chemical compound with the formula CH3I, used as a methylating agent in organic synthesis.