Carbon plays a major role in the structure of life, the condition of the climate and the use of global energy. Plants use photosynthesis to construct sugars out of the carbon from CO2 in the surrounding atmosphere. The carbon in these sugars is what turns into not only an energy source for the plants, but also the biomass of the plants. Students constantly hear about the abundance of CO2 in the atmosphere and that plants are needed to remove this CO2. They rarely have a solid understanding of what happens to that carbon after the photosynthetic process.
This simple study will give students an idea of what happens to the carbon from CO2 once it is absorbed by plants. It will give students a concrete process to begin to think about the rate of photosynthesis controlling the growth of plants and that the biomass of those plants is actually coming from the atmosphere, not the soil.