Photosynthesis requires carbon dioxide and sunlight, but in hot climates, losing water vapor is a serious concern. Succulents have adapted to this by only opening the pores in their leaves (stomata) at night when the sun isn’t shining. They take in carbon dioxide molecules and store them in a unique arrangement until the sun rises, then close up to conserve water. Once the sun is up, the photosynthesis process begins using the available sunlight and the stored carbon dioxide.