AP BIOLOGY

Detailed explanation-1: -Because CAM plants use PEP Carboxylase rather than RUBISCO for the absorption of carbon dioxide, photorespiration does not occur in them.

Detailed explanation-2: -As a result, CAM plants do not need to open their stomata in the daytime to reduce photorespiration because they have already formed a four-carbon molecule at night that can be broken down to release carbon dioxide during the day.

Detailed explanation-3: -Photorespiration does not occur in C4 plants because they have a mechanism that increases the concentration of CO2 at the enzyme site. In the C4 pathway, carbon fixation ultimately results in the production of malic acid in the mesophyll cells. The malic acid is broken down in the bundle sheath to release CO2.

Detailed explanation-4: -Photorespiration presents a major problem for C3 plants because they have no special adaptations to reduce the process.

Detailed explanation-5: -Photorespiration is harmful to C3 plants because it reduces plant productivity, which is why it is also known as a wasteful process. Many higher plants use photorespiration as a means of respiration.