The CAM ( Crassulacean acid metabolism) plants live under arid / very dry environmental conditions. These plants have got specialized adaptation to survive under such conditions. They perform CAM photosynthesis that enable them to conserve water.
They close their stomata during day time and open them during night time to take in carbon dioxide. This prevents water loss during daytime in such plants.
The carbondioxide is stored in vacuoles in the form of four carbon compound called malate.
It is then utilized during day time ( as malate is released out of vacuoles and breaks down to give carbon dioxide that can enter calvin cycle) for performing photosynthesis.
