Microbial Cells First Evolved on Earth Approximately ________ Billion Years

question 44

Multiple Choice

Microbial cells first evolved on Earth approximately ________ billion years ago.

• A) 1.6 to 1.8
• B) 3.8 to 3.9
• C) 5.4 to 5.6
• D) 7.0 to 7.2

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Definitions:

Usable Energy

Energy in forms that can be directly used by humans or converted to other forms of energy for work, including mechanical, electrical, and chemical energies.

Biomass

The total mass of all living organisms in a specific area or volume; often used as a renewable energy source derived from plant and animal material.

Trophic Level

The position an organism occupies in a food chain, defined by the number of steps it is from the primary source of energy (usually the sun); it indicates the organism's role in the transfer of energy and nutrients through an ecosystem.

Water Vapour

The gaseous phase of water, which is invisible and present in the atmosphere, contributing significantly to the greenhouse effect.