How do C4 and CAM plants differ in their photosynthetic processes?

C4 and CAM plants differ in their photosynthetic processes by the way they handle carbon dioxide and manage water loss.

C4 and CAM plants have evolved different strategies to deal with the challenges of photosynthesis, particularly in hot and dry environments. These strategies revolve around the way they handle carbon dioxide (CO2) and manage water loss, which are critical aspects of the photosynthetic process.

C4 plants, such as maize and sugarcane, have a unique way of concentrating CO2 in specific cells to increase the efficiency of photosynthesis. They do this by initially fixing CO2 into a four-carbon compound (hence the name C4) in mesophyll cells. This compound is then transported to bundle-sheath cells, where it releases CO2 for use in the Calvin cycle. This process, known as the C4 pathway, allows these plants to carry out photosynthesis efficiently, even under conditions of high light intensity and temperature.

On the other hand, CAM (Crassulacean Acid Metabolism) plants, like cacti and succulents, have adapted to arid conditions by altering the timing of their photosynthetic processes. They open their stomata (pores on the leaf surface) at night to take in CO2 and store it as a four-carbon compound. During the day, when the stomata are closed to prevent water loss, this compound is broken down to release CO2 for the Calvin cycle. This unique adaptation allows CAM plants to conserve water while still carrying out photosynthesis.

In summary, while both C4 and CAM plants have developed unique ways to optimise photosynthesis under challenging conditions, they do so in different ways. C4 plants concentrate CO2 in specific cells to increase photosynthetic efficiency, while CAM plants alter the timing of their photosynthetic processes to conserve water.