17. C4 Plant

This is a picture of corn. The corn represents a C₄ plant. A C₄ plant utilizes four carbon atoms to convert carbon dioxide into an inorganic compound (carbon fixation). The process in which carbon dioxide is converted into an inorganic compound is more complex than that of a C₃ plant. First, the carbon dioxide reacts with phosphoenolpyruvate (a molecule in which enzymes act upon) in the mesophyll cell (a cell that contains an abundant amount of chloroplast that is necessary to conduct a photosynthesis reaction). The resulting product of the catalyzed phosphoenolpyruvate is oxaloacetic acid, which is then transported to the bundle sheath cells (cells that protect the vascular bundles and is the site where plants utilizes the carbon dioxide to create sugar energy). The oxaloacetic acid loses its carboxyl group, thus releasing carbon dioxide which is utilized in the C₃ pathway. Other examples of C₄ plants include some plants that grow in arid climates like sugarcane.