Which of These Atmospheric Gases Is a Variable Gas (Accounting

question 12

Multiple Choice

Which of these atmospheric gases is a variable gas (accounting for a variable percentage of the atmosphere) ? ​

• A)oxygen
• B)argon
• C)ozone
• D)nitrogen
• E)neon

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Definitions:

Motor Neuron

A type of neuron that transmits signals from the brain or spinal cord to muscles or glands, facilitating movement and action.

Leg Muscle

Muscle groups in the leg, responsible for movement and stability, including the quadriceps, hamstrings, and calves.

Acetylcholine

A neurotransmitter involved in many functions, including muscle contraction and the modulation of alertness, memory, and learning.

Neurotransmitters

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