Spores

(spores) These cells are very resistant due to their thick and very solid shell and can live very long, sometimes even survive in space. As soon as the spore meets acceptable living conditions (humid, moderately warm environment), it germinates and normal fungal or bacterial cells develop. Can spores be killed if they are so resistant? The sheaths are softened by humid heat (steam atmosphere). Not all spores are equally resistant, there are spores that can survive 30 minutes at 121°C in an autoclave. http://www.wasser-wissen.de/abwasserlexikon/s/sporen.htm