The function of the respiratory system is the supply of oxygen rich air to the alveoli and the discharge of carbon dioxide-enriched air. The alveoli are at the end of the airways and have a very thin wall which gases are exchanged with the capillaries. This exchange is based on passive diffusion, inhaled air moves from the alveoli to the blood in the capillaries and carbon dioxide moves from the blood into the alveoli, after which it is exhaled.


Man Gay sapiens or a bipedal primate species in the family Hominidae. Research suggests that modern humans about 200,000 years ago in Africa emerged as a species. Humans have highly developed brains, which he is capable of abstract thinking, language, introspection, problem solving and emotion. Thanks to his intelligence and upright posture, allowing the arms to be free to pick up objects and manipulate, the man much more than other species able to use tools.