What Is the Ratio of Nitrogen to Oxygen in Earth's

question 217

Multiple Choice

What is the ratio of nitrogen to oxygen in Earth's atmosphere?

• A) 1 part nitrogen to 2 parts oxygen
• B) 4 parts nitrogen to 1 part oxygen
• C) 1 part nitrogen to 4 parts oxygen
• D) equal parts nitrogen and oxygen

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Definitions:

Neurotransmitter

Chemical substances in the nervous system that transmit signals across a synapse from one neuron to another.

Serotonin

A neurotransmitter that plays a crucial role in mood regulation, as well as in sleep, digestion, and other bodily functions.

Behaviorist Model

A theory of learning that emphasizes observable behaviors and the ways they're learned through conditioning processes without regard to thoughts or feelings.

Medical Model

A framework for understanding diseases and disorders that emphasizes biological factors and physical processes.