[Campbell Biology P.255] Based on Figure 10.20 and the accompanying text, which statement ac... | Practice Question
Based on Figure 10.20 and the accompanying text, which statement accurately describes the key distinction between C4 and CAM photosynthesis in terms of carbon fixation and the Calvin cycle?
A: In C4 plants, carbon fixation and the Calvin cycle are spatially separated, occurring in different cell types (mesophyll and bundle-sheath, respectively), while in CAM plants, they are temporally separated, occurring at different times within the same cell.
B: Both C4 and CAM plants perform carbon fixation and the Calvin cycle at different times within the same cell.
C: C4 plants separate carbon fixation and the Calvin cycle by time, whereas CAM plants separate them by space.
D: C4 plants primarily fix CO2 at night, and CAM plants fix CO2 during the day.
Explanation
Figure 10.20 and the text explicitly state that C4 plants show spatial separation of carbon fixation and the Calvin cycle mesophyll vs. bundle-sheath cells , while CAM plants exhibit temporal separation night vs. day within the same cell .