=====Concentration Gradients (p.24) ======
1) The oxygen concentration in the alveoli is not as high as in fresh air that is inhaled because some of the oxygen concentration may have been released by diffusion through the capillaries. There are also cells in the epithelium that may secrete a surfactant, helping oxygen to dissolve.
2) a) ((105 – 40)/40 )*100 = 163%
c)( i) ((3-27)/3)* 100 = 800% : Thus, theres a 800% difference in carbon dioxide concentration between air inhaled and air exhaled.
c) (ii) The difference can be seen because the carbon dioxide is diffusing out of the blood to travel to alveoli. This would ultimately increase the amount of carbon dioxide as well.
d) Despite the high concentration of nitrogen in air in alveoli, little or none diffuses from the air to the blood because nitrogen is not processed in any part of the body which would explain why nitrogen levels may be similar in the air and blood. Though we can see that nitrogen stays at a high amount in each aspect of figure 4.