Ladybell flower pistil. Coloured scanning electron micrograph (SEM) of a ladybell flower (Adenophora triphylla) pistil. Pollen grains (round, green) are seen on the pistil. Pistils hold a plant's female reproductive structures. They contain one or more carpels, which, in turn, contain a stigma, style and an ovary. Within the ovaries are the ovules, the female gametes (sex cells). The ovaries are fertilised by pollen grains, the male gametes. Magnification: x100 when printed at 10 centimetres wide.