Electron micrographs of a bovine granulosa cells. Electron micrographs of a bovine granulosa cells with high nuclear:cytoplasm ratio at 0h of culture (A; 0h of culture; magnification: x 6800) and elongated cell with low nuclear:ctoplasm ratio that was randomly found in the culture (B; 96h of culture; magnification: x 2720). Note the high concentration of lipid droplets and smaller nucleus in the elongated cell. Bovine granulosa cells presented polyhedral shape, dispersed lipid droplets, and mitochondrias with tubovesicular cristae. (C; 48h; magnification bar: x 8500). Neighboring cells within the cluster had rough endoplasmic reticulum, free ribosomes and cellular communication described as tight junctions (D; 48h; magnification bar: x 12500). mi = mitochondria; li= lipid droplets; n=nucleus; c= cytoplasm, rer= rough endoplasmic reticulum; r= ribosomes, arrow=tight junctions.