[Campbell Biology P.994] According to Figure 42.26 and its description, which statement accu... | Practice Question

According to Figure 42.26 and its description, which statement accurately describes the flow of air during the second inhalation in a bird's respiratory cycle?

  • A: Air fills the posterior air sacs.
  • B: Posterior air sacs contract, pushing air into lungs.
  • C: Air passes through lungs and fills anterior air sacs.
  • D: Anterior air sacs contract, pushing air that entered body at first inhalation out of body.

Explanation

According to Figure 42.26 and the accompanying text, the second inhalation Step 3 in a bird's respiratory cycle involves air passing through the lungs and filling the anterior air sacs.