Large Amounts of Oxygen Gas First Appeared in Earth's Atmosphere

question 27

Multiple Choice

Large amounts of oxygen gas first appeared in Earth's atmosphere about ________ years ago.

• A)500,000
• B)10 million
• C)2)7 billion
• D)3)5 billion

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Definitions:

Photoreceptors

Specialized cells in the retina of the eye that are sensitive to light and enable vision by converting light into electrical signals that can be interpreted by the brain.

Environmental Energy

The sum of all the renewable and non-renewable energy resources and their potential to be harnessed by organisms, including humans, within an environment.

Sensory Receptor Neurons

Specialized neurons that detect changes in the environment (such as light, sound, touch) and transmit information about those changes to the nervous system.

Neural Activity

The sum of all electrical and chemical processes occurring within neurons, including action potentials and synaptic transmissions.