Fig. 1

Early development of an Arabidopsis thaliana zygote [1]. Each unit is a cell. A green line between two cells means these two cells were just generated by a symmetric horizontal division. A blue line between two cells means these two cells were just generated by a symmetric vertical division. A red line between two cells means these two cells were just generated by an asymmetric division. An orange circle in a cell means this cell did not divide during the last stage