Azalea pollen. Coloured scanning electron micrograph (SEM) of pollen of an Azalea on a flower pistil. Pollen contains the male sex cells of a plant. When it lands on the female pistil, it sprouts pollen tubes, which burrow down through the pistil to reach the ovary, where it fertilises the ovum (egg cell). Magnification: x285 when printed 10cm wide.