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.
The carbon cycle explains how carbon is made available to life forms. The main processes of the carbon cycle are photosynthesis, respiration, decomposition, natural weathering of rocks and burning fossil fuels. Primary producers use photosynthesis to take in carbon. Plants absorb it from the atmosphere in the form of carbon dioxide. Carbon moves up the food chain when animals feed on plants and the carbon is transferred. While alive, animals release carbon dioxide back into the atmosphere through respiration. After an organism has died, the carbon is recycled by decomposers.