Question

The partial pressure of oxygen changes with barometric pressure.
a.True
b.False

Answer 1

False. The partial pressure of oxygen in the lungs is lower than in the external air due to two major mechanisms: a smaller difference in partial pressures between the alveoli and the blood, and the production of more BPG at high altitudes.

Step-by-step explanation:

The partial pressure of oxygen changes with barometric pressure: False.

The partial pressure of oxygen in the lungs is lower than in the external air due to two major mechanisms:

1. A smaller difference in partial pressures between the alveoli and the blood, resulting in less oxygen crossing the respiratory membrane and binding to hemoglobin.
2. At high altitudes, a greater amount of BPG is produced by erythrocytes, enhancing the dissociation of oxygen from hemoglobin.