Cellular respiration and photosynthesis are important parts of the carbon cycle. The carbon cycle is the pathways through which carbon is recycled in the biosphere. While cellular respiration releases carbon dioxide into the environment, photosynthesis pulls carbon dioxide out of the atmosphere. The exchange of carbon dioxide and oxygen during photosynthesis (Figure below) and cellular respiration worldwide helps to keep atmospheric oxygen and carbon dioxide at stable levels.
I think carbon dioxide then sugars
DNA can illustrate that evolution has occurred since in the process of natural selection advantegeous genes or traits have been selected to pass on through generations and further more evolve as long as the species survies and is successful in reproducing.
