How Old Are the Oldest Known Fossils

question 79

Multiple Choice

How old are the oldest known fossils?

• A) 30-40 million years old
• B) 400-500 million years old
• C) 800-900 million years old
• D) 1-2 billion years old
• E) 3-4 billion years old

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Definitions:

Chemical Structure

The arrangement of atoms in a chemical substance and the chemical bonds that hold those atoms together, determining the substance's properties.

Sensory Adaptation

The process by which the sensitivity to a stimulus declines if the stimulus is presented for an extended period of time.

Stimulus

Any event or situation that evokes a response from an organism.

Sensory Apparatus

The complex of sensory organs and parts an organism uses to detect changes in its environment.