Scots pine (Pinus sylvestris) male cone. Light micrograph of a section through a male cone from a Scots pine tree, showing its pollen. The cone axis (blue-red) bears a pouched walled of microsporangium (red), within which the pollen is produced. The pollen grains each have a large air bladder, which gives buoyancy in the air and aids wind dispersal. Magnification: x5 when printed 10 centimetres wide.