Pollen magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics. Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower. Pollen itself is not the male gamete. Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive)
Enteric coating However, as the solvents for such solutions are organic solvents, there's a concern about the toxicity potential of the traces of the residual solvents in the tablet coating. The first form of gastro-resistant coating was introduced by Unna in 1884 in the form of keratin-coated pills, although it was later discovered that they weren't able to withstand gastric digestion. Salol was also used by Ceppi as one of the first forms of enteric coating. However, the first material that was extensively used as enteric coating agent was shellac, since its introduction in 1930. Properly treated or hydrolyzed shellac showed different