Question

In which direction would oxygen diffuse if it’s partial pressure in the blood were 40 MM Hg and it’s partial pressure in the alveoli 35MM Hg? how would this affect homeostasis overall?

Answer 1

Gas exchange in lung occurs between alveoli and the blood. This oxygen and carbon dioxide perfusion depends on the partial pressure of the gases in both places. If the oxygen partial pressure in blood is 40mm Hg and it in alveoli is 35 mm Hg, which means ventilation is insufficient. i.e., there is less oxygen saturation in alveoli of lungs compared to oxygen saturation in the blood. So there won’t be any perfusion of oxygen from alveoli to blood (perfusion occurs from place of higher partial pressure of a gas to lower partial pressure) .Instead oxygen will flow from blood to alveolar area.

Maintaining high partial pressure of oxygen in lungs helps for perfusion of oxygen to blood. If it doesn’t happen it will lead to imbalance in the homeostasis of body. Perfusion of oxygen to blood is very important as it breaks the food particle and releases energy for the body activities .due to decrease perfusion of oxygen into blood, blood pH decreases leading to acidosis .Respiratory acidosis can lead to metabolic acidosis which causes imbalance of normal homeostasis of body.