Orbicule

Orbicules (syn. Ubisch bodies, con-peito grains) are small acellular structures of sporopollenin (known size range from < 1 µm to 15 µm, but usually sub-micrometre) that might occur on the inner tangential and radial walls of tapetal cells. Their function is unclear at this moment. Current consensus is that they are just a by-product of pollen wall sporopollenin synthesis.

External links

• A photo of Nelumbo orbicules: Kreunen, S.S. & Osborn, J.M. (1999), "Pollen and Anther Development in Nelumbo (Nelumbonaceae)(figure 32)", American Journal of Botany, 86 (12): 1662–1676, doi:10.2307/2656664, JSTOR 2656664, PMID 10602759