How Long Did the Proterozoic Eon Last

question 71

Multiple Choice

How long did the Proterozoic eon last?

• A)approximately 500 million years
• B)approximately 1 billion years
• C)approximately 2 billion years
• D)approximately 4 billion years

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Definitions:

Genus Rhizobium

A group of soil-borne bacteria that form symbiotic relationships with leguminous plants, fixing nitrogen in nodules on their roots.

Bacteria

Microscopic, single-celled organisms that exist in diverse environments and can have roles ranging from decomposing dead matter to causing disease.

Nitrogen

A chemical element with symbol N, atomic number 7; a colorless, odorless unreactive gas that forms about 78% of the earth's atmosphere and is a constituent of all living tissues.

Coriolis Effect

A deflection of moving objects when they are viewed in a rotating reference frame, often observed in the movement of air masses on Earth, influencing weather patterns and ocean currents.