What is the difference between C3, C4, and CAM photosynthesis?

C3, C4, and CAM photosynthesis differ in their carbon fixation pathways and the way they minimize water loss.

C3 photosynthesis is the most common type and occurs in most plants. It involves the fixation of CO2 into a three-carbon molecule, which is then used to produce glucose. However, C3 plants are less efficient in hot and dry environments as they lose water through transpiration.

C4 photosynthesis is a more efficient pathway that evolved in plants living in hot and dry environments. It involves the initial fixation of CO2 into a four-carbon molecule, which is then transported to specialized cells where it is converted back to CO2 for use in the Calvin cycle. This process reduces water loss and allows for more efficient photosynthesis.

CAM photosynthesis is a variant of C4 photosynthesis that occurs in succulent plants such as cacti and agaves. These plants open their stomata at night to take in CO2, which is then stored as a four-carbon molecule. During the day, the stomata are closed to reduce water loss, and the stored CO2 is used in the Calvin cycle.

In summary, C3 photosynthesis is the most common type, while C4 and CAM photosynthesis are adaptations to hot and dry environments that minimize water loss and increase efficiency.