Combinations of characteristics observed in Physcomitrella knock-out library transformants. A, 16,203 Physcomitrella plants resulting from transformation with the gene-knockout library were assessed for morphological deviations, retarded growth on minimal medium, and ploidy level . Absolute numbers as well as relative percentages for each of the eight possible combinations of attributes are shown in the table. B, Graphic representation of the observed combinations of attributes. The three characteristics assayed for each transformant are represented by the three dimensions of a cube. Spheres at the corners of the cube denote the eight possible combinations of characteristics; their volume is proportional to the number of transformants observed for each class.