Transport of Gases

• The gas exchange through the alveoli membrane and capillaries occur by simple diffusion
• Fick's law describes transalveolar gas exchange VO2=DO2 A(PalO2-ParO2)t
• t is the transalveolar thickness
• The path lenght for diffusion includs the thickness of the alveolar epithelium and underlying basement membrane and the capillary endotheliumç
• Respiratory pigments in blood often transport O2 from the respiratory surface to the tissues but can also transfer 02 from blood into cells or act as intracellular oxygen stores such as myoglobi and neuroglobins.
• increase temperature increase dissociation of oxygen from hemoglobin.
• 2-3 Diphosphoglycerate in erhythrocyte; it increase dissociation of oxygen from hemoglobin.
• The rate of 02 transport by the circulatory system depends on the rate of blood flow and the O2 contents of arterial blood and venous blood.