Regola o caso speciale? Franz Unger (1800-1870) e la scoperta della divisione cellulare

The concept of cell division marks a greater paradigm change in the history of the life sciences because it transformed ideas of the formation of living substance into ideas of reproduction of living substance. The process of cell division had been observed, described and even investigated since the late nineteenth century, yet it was not before the 1850s that it was conceived as the exclusive way of cell multiplication. An analysis of the works of the Austrian botanist Franz Unger, in the 1830s one of the pioneers of cell theory, shows that a series of reasons – the research techniques, the power of tradition, the choice of the research objects, and the prevailing cell definition – induced the leading plant anatomists of this period to conceive cell division as an exception and not as a rule.