AP BIOLOGY

Detailed explanation-1: -Rubisco can bind to either carbon dioxide or oxygen depending on environmental conditions. Binding to carbon dioxide and initiation of the Clavin cycle is favored at low temperatures and at a high carbon dioxide-to-oxygen ratio.

Detailed explanation-2: -Rubisco aims to fix carbon dioxide, but can also fix oxygen molecules, which creates a toxic two-carbon compound. Rubisco fixes oxygen about 20 percent of the time, initiating a process called photorespiration that recycles the toxic compound.

Detailed explanation-3: -In C3 plants, RuBisCO occurs in mesophyll cells, whereas in C4 plants RuBisCO is present in bundle sheath cells.

Detailed explanation-4: -The Calvin cycle is employed to fix carbon in the mesophyll cell of C3 plants, and RuBisCO is present there.

Detailed explanation-5: -Photorespiration is the process where RuBisCO binds to oxygen instead of CO2. This process is another reason that RuBisCO is not as efficient as many other enzymes.