The poster illustrates how carbon is exchanged between the atmosphere, geosphere, biosphere, and hydrosphere. Cellular respiration in an organism (plants and animals) -biosphere- produce carbon dioxide as a waste product. This carbon dioxide is released into the atmosphere. Plants then take up this carbon dioxide during photosynthesis and return the carbon from the atmosphere back to the biosphere. The carbon dioxide in the atmosphere also dissolves in and out of the hydrosphere (oceans and seas) and the dissolved carbon dioxide is fixed by the photosynthetic organisms (algae) to organic carbon. Volcanos and fossil fuels (geosphere) also contribute to spewing out of carbon dioxide into the atmosphere. This carbon will also get into the biosphere by photosynthesis.
