Alveolar Gas Partial Pressures at Rest

Multiple Choice

Alveolar gas partial pressures at rest

A) Are relatively constant because the tidal volume is a small fraction of the FRC
B) Vary widely during each breath because fresh air replaces “stale” alveolar air during each
breath
C) Vary widely because the blood squirts through unevenly during each ejection cycle of the
heart
D) Are the sam e as those in moist tracheal air
E) Are relatively constant because the tidal volume is a small fraction of the TLC