Sunflower pollen. Coloured scanning electron micrograph (SEM) of pollen grains of the sunflower (Helianthus annuus). The outer wall (exine) of each pollen grain has a spiky structure, and these surface projections may serve to adhere the pollen to insect pollinators. The pollen carries the male genetic information of the plant. It is transferred to the stigma of a flower, where it fertilises the ovules in the female ovary to form seeds. Magnification: x1000 at 6x7cm size.