Rose pollen. Coloured scanning electron micrograph (SEM) of tricolporate pollen grains of a Garden Rose, Rosa sp. Pollen grains are the male sexual spores that are discharged from the male part of the flower. They contain the gamete that ferti- lizes the female ovule to form a seed. Pollen grains are classified according to a number of features: pores (porate), furrows (colpate), or both (colporate). Rose pollen has three furrows from each of which protrudes a bulge or pore (as seen here). They are thus tricolporate". Rose plants are insect pollinated, relying on insects to carry the pollen to the female flower structures. Magnification: x1,000 at 5x7cm size. Magnification: x2000 at 11x16cm size."