Fractionation of carbon isotopes in oxygenic photosynthesis Calvin cycle during the day, when stomata are closed to prevent water loss, and the light reactions can drive the necessary ATP and NADPH production. This pathway differs from C4 photosynthesis because CAM plants separate carbon by storing fixed CO in vesicles at night, then transporting it for use during the day. Thus, CAM plants temporally concentrate CO to improve Rubsico efficiency, whereas C4 plants spatially concentrate CO in bundle sheath cells. The distribution of plants which use CAM photosynthesis includes epiphytes (e.g., orchids, bromeliads) and xerophytes (e.g., succulents, cacti). In Crassulacean acid metabolism, isotopic fractionation combines the effects of
What I Need to Do What I Need to Do "What I Need To Do" is a song written by Tom Damphier and Bill Luther, and recorded by American country music artist Kenny Chesney. It was released in January 2000 as the fourth and final single from Chesney's 1999 album "Everywhere We Go". The song peaked at number 8 in the United States and number 13 in Canada in 2000. The song describes the narrator thinking about "what [he] need[s] to do" as he is driving away from his old hometown away from his former lover. He also thinks that he should "turn [his] car