Why Is the Actual Flow of Air into the Alveoli

question 26

Multiple Choice

Why is the actual flow of air into the alveoli during inspiration passive?

• A) because there is a continuous column of air from the pharynx to the alveoli
• B) because the lungs are surrounded by the thoracic wall
• C) because the alveoli have a very large surface area
• D) because the intercostal muscles are involved
• E) because the diaphragm is involved

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Definitions:

Second Messenger

Intracellular signaling molecules released by the cell in response to exposure to extracellular signaling molecules.

Intercellular Signals

Chemical or physical messages passed between cells to coordinate their activities and functions within an organism.

Coordinate Growth

The process by which various parts of an organism grow at rates that maintain the overall shape and proportion of the organism.

Endocrine Stimulation

The activation or increase of hormonal activity by the endocrine glands in the body.