The Lack of Any Obvious Source for Many Outflow Channels

question 91

Multiple Choice

The lack of any obvious source for many outflow channels on Mars suggests that the water originated from

• A) underground
• B) the atmosphere in the form of rain
• C) ancient melting glaciers
• D) the atmosphere in the form of snow

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Definitions:

Amines

Organic compounds and functional groups that contain a basic nitrogen atom with a lone pair.

Genetic Material

The molecules responsible for inheritance and the biological characteristics of organisms, primarily DNA (deoxyribonucleic acid) and RNA (ribonucleic acid).

DNA

The molecule that carries genetic instructions used in the growth, development, functioning, and reproduction of all known living organisms and many viruses.

Zygote

The initial cell formed when a new organism is produced by sexual reproduction, resulting from the union of sperm and egg cells.