Question

Explain how the PO₂ differences in the systemic and pulmonary capillaries affects carbon dioxide transport in the blood.

Answer 1

The purpose of respiratory system is to perform gas exchange. Pulmonary ventilation provides air, to the alveoli for exchange of gases At respiratory membrane Calveolas and capillary wall meet) gases move across the membrane where oxygen entersblood stream and CO2 exists. Ventilation & the exchange of air between the lenge and the atmosphere so that oxygen can be exchanged for CO2 in the alreoli Pesfusion is the passage of fluid through cioculatory system to an organ/ a tissine. Mechanism of Gas exchange The partial pressure of oxygen is alreoli ß 10 among The partial pressure of oxygenated pulmonary venous blood is about 100 mm Hg. When the ventilation is sufficient orygen enters the alveoli at high rate and partial pressure of orygenin alveoli remain high. When ventilation finsufficient, partial pressure of oxygen in alveoli drops

Without the large difference in partial pressure between alveoli and blood oxygen does not diffuse effeciently accross respiratory membrane When ventilation ß not sufficient for alveokes, the body redirects blood into alveoli that are receiving I sufficient ventilation This procedure is achieved by constricting the - pulmonary arterioles which redirects the blood jlow to alneoli that are receiving sufficent ventilation At the same time, the pulmonary arterioles that Seene alveoli recelning beu sufficient ventilation vasodilate which brings in greater blood flow. Ventilation is regulated by diameter of airways Perfusion is regulated by diameter a blood ressele. Alveolus Blood capillaries out