Understanding the differences between C3, C4, and CAM plants is essential for grasping how plants adapt to their environments, particularly in relation to photosynthesis and photorespiration. Photorespiration is a process that can hinder photosynthesis by wasting energy in the form of ATP and NADPH while producing carbon dioxide (CO₂), which is counterproductive to the photosynthetic process that aims to utilize CO₂.

C3 plants are particularly vulnerable to photorespiration, especially in hot temperatures. This vulnerability arises because, under such conditions, C3 plants tend to close their stomata to prevent water loss, which inadvertently limits gas exchange and increases the likelihood of photorespiration. In contrast, C4 and CAM plants have developed specialized mechanisms to minimize photorespiration, allowing them to thrive in hotter climates.

C4 plants utilize a unique pathway that effectively concentrates CO₂ in their leaf cells, reducing the chances of photorespiration. This adaptation enables them to maintain efficient photosynthesis even when stomata are closed. Similarly, CAM (Crassulacean Acid Metabolism) plants take in CO₂ at night, storing it as organic acids, which are then used during the day for photosynthesis while the stomata remain closed to conserve water.

In summary, while C3 plants are more susceptible to the inefficiencies of photorespiration, C4 and CAM plants have evolved strategies that allow them to minimize this process, making them better suited for survival in hot environments. This understanding sets the stage for a deeper exploration of the specific mechanisms and adaptations of these plant types in subsequent discussions.