Fig. 3.
Simulation of cell arrangement patterns with the RO-only model. (A) Schematic representation of the RO model. The upper panel shows the repulsive forces between the cells (blue arrows) and between the cells and the eggshell (red arrow). The lower panel shows the orientation and timing of cell divisions. (B) Relationship between strength of intercellular force (Fij) and cell–cell distance (dij) in the RO model. (C) Examples of the cell arrangement patterns at the four-cell stage as simulated by the RO model at AR=1.1, 1.6, 2.2 and 2.6, respectively. The black circle represents AB daughter cells; the green, the EMS cell; and the red, the P2 cell. The magenta circle represents the centroid of the cells. (D) Relationship between the percentage of different patterns of cell arrangements found and the ARs in the RO model (blue, diamond type; red, pyramid type; cyan, linear type).