It is possible to have multiple independent variables and/or multiple dependent variables. For instance, in multivariable calculus, one often encounters functions of the form, where z is a dependent variable and x and y are independent variables.
Gas exchange between the air within the alveoli and the pulmonary capillaries occurs by diffusion. The oxygen must first dissolve before passing through the respiratory epithelium. Gas moves from a region of high partial pressure to a region of low partial pressure, down a partial pressure gradient.
When the lungs fill with air, oxygen diffuses through the alveoli walls from the inhaled air into blood cells, exchanging with carbon dioxide, which diffuses out to the inhaled air from the blood cells.osted on. (Answer #1). Oxygen is absorbed in the lungs and transported all over the body by blood; when the blood releases its oxygen, it absorbs carbon dioxide (waste) and transports that back to the lungs, where it is expelled. This process is called respiration.