Re: How do CAM plants differ from C3 and C4 plants?

Basically, CAM plants open their stomata at night and fix carbon dioxide first
as a 4-carbon organic acid, such as malic acid. In the light, they close their
stomata and obtain carbon dioxide from the stored malic acid to use in the
Calvin cycle of photosynthesis. This adaptation saves water so is found mainly
in plants that live in environments where water availability is limited, such as
many cacti and  bromeliads, some orchids and other succulents. 

Pineapple and kalanchoe are two familiar CAM plants. Several Kalanchoe species
are grown as houseplants. Kalanchoe are also popular flowering potted plants.
There are other interesting aspects of CAM photosynthesis such as CAM idling,
CAM cycling and obligate CAM plants.

Stomata open in the light and close at night for C3 and C4 plants. C4 plants
first fix carbon dioxide as 4-carbon organic acids using the enzyme PEP
carboxylase. This occurs in the light in their mesophyll cells. The organic acid
is then transported into specialized bundle sheath cells where it is broken
apart to release the carbon dioxide. This carbon dioxide is then fixed via the
Calvin cycle. 

C3 plants use just the Calvin cycle so their first stable carbon fixation
product is a C3 compound, not a C4. All three types of photosynthesis use the
Calvin cycle to fix carbon dioxide. Most plants are C3 plants.

There are many webpages that discuss CAM photosynthesis in greater detail.
Search google.com to locate them. Also check the madsci archive.

References


Re: can carbon dioxide from cellular respiration be used


Re: In xerophytes what happens to the oxygen liberated in photosynthesis?