Which of the Following Is True Regarding Normal Quiet Expiration

question 55

Multiple Choice

Which of the following is true regarding normal quiet expiration of air?

• A) It depends on the complete lack of surface tension on the alveolar wall.
• B) It is a passive process that depends on the recoil of elastic fibers that were stretched during inspiration.
• C) It requires contraction of abdominal wall muscles.
• D) It is driven by increased blood CO₂ levels.

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Definitions:

Refractory Period

A period immediately following stimulation during which a nerve or muscle is unresponsive to further stimulation.

Action Potential

A brief electrical impulse that enables the transmission of signals along the neuron, crucial for nerve impulse propagation.

Above-Threshold

Pertaining to a stimulus strength that is sufficient enough to be detected or to produce a response.

Depolarizing Current

An electrical current that reduces the membrane potential of a neuron, making it more likely to fire an action potential.