[Campbell Biology P.994] The 'WHAT IF?' section poses a question about the loss of elastic f... | Practice Question

The 'WHAT IF?' section poses a question about the loss of elastic fibers in alveolar walls. If these fibers were lost, how would this primarily affect gas exchange efficiency in the lungs?

  • A: It would lead to a significant increase in vital capacity due to easier expansion.
  • B: The ability of alveoli to fully recoil and expel air would be impaired, hindering efficient exhalation and potentially gas exchange.
  • C: Inhalation would become completely passive, requiring no muscle work.
  • D: The surface area for gas exchange would increase dramatically.

Explanation

The 'WHAT IF?' section implies that elastic fibers allow alveoli to expand and contract. Their loss would mean the alveoli lose their natural recoil, making it difficult to fully expel air during exhalation. This impaired exhalation would hinder the efficient removal of carbon dioxide and intake of oxygen, thus affecting gas exchange.