Final answer:
CAM (Crassulacean Acid Metabolism) enables plants to reduce water loss by transpiration by opening their stomata at night and closing them during the day, thus conserving water and adapting to arid environments.
Step-by-step explanation:
Crassulacean Acid Metabolism, commonly known as CAM, is an adaptive photosynthetic pathway found in certain plants such as sedum, cacti, jade plants, and some orchids, which help these plants significantly reduce the loss of water by transpiration. These plants are often located in arid environments, where water conservation is crucial for survival.
CAM plants exhibit a unique mechanism where they open their stomata at night to minimize water loss due to the cooler temperatures, which allows them to uptake CO2 and fix it as organic acids. During the day, the stomata are closed, helping to conserve water. This stored CO2 is then re-fixated into carbohydrates using the energy from the light reactions during the day.
This adaptive strategy is particularly beneficial during high daytime temperatures where open stomata would otherwise lead to a significant loss of water. By fixing CO2 at night and conducting the Calvin cycle during the day with closed stomata, CAM plants efficiently conserve water while still maintaining the photosynthetic process.