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 U Need? What U Need? "what U need?" is a single recorded by Chinese singer Lay for his debut extended play "Lose Control" . It was pre-released on October 7, 2016 by S.M. Entertainment as a birthday gift for Lay's fans. Produced by Devine Channel and Lay, "what U need?" is described as a "Pop-R&B" song with lyrics about being overwhelmed by a loved one. "what U need?" music video was released on October 7, 2016. It features Lay with backup dancers dancing the song's choreography. Lay performed "what U need?" for the first time on October 9 at the 2016 Asia