Question

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> Which of the following statements is true?

• A. Exhaled air contains more oxygen and less carbon dioxide than inhaled air.
• B. Exhaled air contains less oxygen and less carbon dioxide than inhaled air.
• C. Inhaled air contains equal amount of carbon dioxide and oxygen than exhaled air.
• D. Exhaled air contains more carbon dioxide and less oxygen than inhaled air.

Answer 1

The correct option is D Exhaled air contains more carbon dioxide and less oxygen than inhaled air.

Oxygen is required for respiration. We inhale air, and oxygen from this is used for respiration. During respiration, carbon dioxide is released. This carbon dioxide is sent out through exhalation.
Inhaled air contains 21% oxygen and 0.04% carbon dioxide.
Exhaled air contains 16.4% oxygen and 4.4% carbon dioxide.