Fig. 5. Effect of CYC on Arabidopsis petal cell size. SEM images of the tip and middle areas of wild-type and 35S::CYC:GR petals show that the increase in petal area when CYC is active is due to an increase in cell size. In each SEM image, the same number of cells are highlighted in orange. Numbers indicate cell size (µm²±s.e.m.) in the tip and middle regions of the petals, determined using the CellFinder programme. On average between 200 and 500 cells were measured per image and five petals were used to obtain the average cell size in the different petal areas. Left panel shows wild-type and right panel shows 35S::CYC:GR plants (+CYC) grown with DEX. Scale bar: 50 µm on the SEM images; 1 cm on the whole petals.