Scanning electron micrograph of pollen grains from Agapanthus, commonly known as "African lily" or "Lily of the Nile". Pollen grains contain the male gamete and are produced by the anther in a flower. They are transferred from one flower to another (pollination) so that fertilization of the female gametes can occur (sexual plant reproduction). Pollen is a common trigger of hay fever or seasonal allergies. Horizontal width of image is 250 micrometres. Supplied by Kevin Mackenzie, courtesy of Wellcome Images.