ABSTRACT
Plant cell and tissue culture is based on direct visual observation, unlike other disciplines, such as molecular genetics, virology, and physiology, where the results from experiments are often abstract. With
in vitro
culture, the confirmation that the experimental response has occurred is based primarily on visual proof. For example, the scientist determines whether or not cultured tissue has undergone embryogenesis or organogenesis by looking for the presence of somatic embryos or organs. Thus, the fundamental documentation of plant cell and tissue culture research is often a photograph.
