During exhalation of the first breath, the lungs do not collapse completely again in a newborn infant because
A)surfactant covering the alveolar surfaces prevents their collapse.
B)exhalation is never as forceful as is inhalation.
C)cartilages and connective tissues keep the conducting passageways closed.
D)the incoming air is warmed by the upper portion of the respiratory tract, and this causes the lung tissues to expand and remain larger in size than previously, even when emptied of air.
E)None of the answers are correct.

Question

Quizplus · Accepted Answer

Surfactant is a phospholipid that reduces the surface tension of water in the alveoli, preventing their collapse and allowing for easier expansion and contraction. It is produced by type II alveolar cells and is critical for respiratory function, particularly in premature infants who may not have enough surfactant developed yet.

During Exhalation of the First Breath, the Lungs Do Not