A CAM Plant is a plant that survives in arid areas due to its ability to use a Crassulacean Acid Metabolism (CAM) System. This process allows the plant to draw carbon dioxide at night and produce organic acids which aid in its survival. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide. The CO2 is stored as the four-carbon acid malate, and then used during photosynthesis during the day. There are four different division of CAM Plants which include; the Lycopodiophyta, the Magnoliophyta, the Pteridophyta and Cycadophyta.