it's been a while meaning, it's been a while definition | English Cobuild dictionary. been. 1 Been is the past participle of be. 2 verb If you have been to a place, you have gone to it or visited it. He's already been to Tunisia, and is to go on to Morocco and Mauritania...
Carbon dioxide is a by-product of respiration ] and combustion combustion: Combustion is the process of burning by fire. . Green plants remove carbon dioxide from the atmosphere by photosynthesis. Living organisms-including all plants and animals-release energy from their food using respiration.Respiration and combustion-burning-both release carbon dioxide into the atmosphere.These processes form a carbon cycle in which the proportion of carbon dioxide in the atmosphere remains about the same.The animation should help you to understand how the cycle works.espiration and combustion-burning-both release carbon dioxide into the atmosphere. These processes form a carbon cycle in which the proportion of carbon dioxide in the atmosphere remains about the same.
Photo by: Creations. Respiration is the process by which living organisms take in oxygen and release carbon dioxide. The human respiratory system, working in conjunction with the circulatory system, supplies oxygen to the body's cells, removing carbon dioxide in the process. The exchange of these gases occurs across cell membranes both in the lungs (external respiration) and in the body tissues (internal respiration). Breathing, or pulmonary ventilation, describes the process of inhaling and exhaling air. The human respiratory system consists of the respiratory tract and the lungs.