Flower reproductive parts. Coloured scanning electron micrograph of the reproductive parts of a fan columbine (Aquilegia flabellata) flower. The male stamens comprise a long filament bearing an oval anther. The anthers produce the flower's pollen, the male sex cells. At the centre of the stamens are the stigmas of the female carpel. Pollination occurs when pollen lands on the stigma. It then burrows down through the style to reach the female sex cell (ovum) in the ovary (not seen) at the base of the carpel.