6.4.1 Distinguish between ventilation, gas exchange and cell respiration

Ventilation is the process of inhaling (breathing in) and exhaling (breathing out) air, which is controlled by the diaphragm and the ribcage, or intercostals muscles.

  

Gas exchange is the diffusion of oxygen and carbon dioxide between the alveoli and the capillaries surrounding it. There are two steps: first oxygen diffuses into the capillaries from the alveoli and carbon dioxide diffuses out of the capillaries into the alveoli, second the oxygen diffuses from the blood in the capillaries into the cells and carbon dioxide diffuses out of the cell into the blood. 

All diagrams: (http://www.emc.maricopa.edu/faculty/farabee/biobk/biobookrespsys.html)

Cell respiration is what happens within the cell for the production of ATP. There is aerobic respiration, which uses oxygen, and anaerobic, which does not.

(http://www.phschool.com/science/biology_place/biocoach/images/cellresp/Overview.gif)