C₄ plants differ from C₃ and CAM plants in that C₄ plants _____. a. transfer fixed carbon dioxide to cells in which the Calvin cycle occurs b. use malic acid to transfer carbon dioxide to the Calvin cycle c. are better adapted to wet conditionsd. use PEP carboxylase to fix carbon dioxide e. open their stomata only at night

In C4 plants the light reaction and Calvin cycle occurs in two different cell that are mesophyll cell and bundle sheath cells. First, the CO₂ is fixed into 4- carbon oxaloacetate by an enzyme PEP carboxylase.

Then this oxaloacetate is converted into a simpler form called malate. Malate molecule then enters into bundle sheet cell and there it releases one molecule of CO₂. This CO₂ enters the Calvin cycle which results in the sugar formation with the help of enzyme rubisco.

Therefore by releasing of CO₂ molecule by malate in bundle sheet cells, it transfer fixed carbon for the Calvin cycle to occur.