Question

from which part of the lung oxygen diffuse into the blood

Answer 1

Dear student, The wall of alveoli is very thin and has rich network of blood capillaries. The partial pressure of oxygen in the alveoli is higher (104 mm Hg) than that in the deoxygenated blood in the capillaries of the pulmonary arteries (95 mm Hg). As the gases diffuse from a higher to a lower concentration, the movement of oxygen occurs from the alveoli to the the blood. The partial pressure of carbon dioxide is higher in deoxygenated blood (45 mm Hg) than in alveoli (40 mm Hg), therefore, carbon dioxide passes from the blood to the alveoli. So from alveoli the oxygen diffuses from lungs to blood. Thanks and regards