• 2022-06-11
    Which of the following is NOT true of the alveolar sac
    A: Directly communicates with the alveolar duct
    B: Has an interrupted wall represented by knobs between adjacent alveoli
    C: The space surrounded and opened by many alveoli
    D: Connective tissue fibers encircle the openings of the alveoli
    E: Smooth muscle disappears in this segment