Which statement correctly distinguishes ventilation from respiration?

• A. Ventilation is the movement of carbon dioxide between lungs and blood.
• B. Ventilation involves moving gases between inhaled air and blood; Respiration involves moving oxygen between blood and cells.
• C. Ventilation is cellular energy production.
• D. Respiration is the movement of air into the lungs.

Answer: (B)

Ventilation is the physical movement of air into and out of the lungs, delivering air to the alveoli so gases can be exchanged. Respiration refers to gas exchange at the tissue level: oxygen moves from blood into the cells and carbon dioxide moves from cells into the blood (and then be expelled by the lungs). The correct statement captures this separation: ventilation involves moving gases between inhaled air and blood, while respiration involves moving oxygen between blood and cells. This aligns with how we understand external gas exchange in the lungs and the delivery of oxygen to body tissues.

The other ideas mix up these processes: moving CO2 between lungs and blood is part of gas exchange, not ventilation itself; cellular energy production is metabolism (cellular respiration), not ventilation; and moving air into the lungs describes ventilation, not respiration.