Fig. 9. Ea and Ep polarity directs the movement of their neighbors. On the left side of each panel is a schematic drawing of part of a P₁ isolate and the experiment performed. Cells in the isolates were separated at the site indicated by the broken line, rotated along an axis (unbroken gray line in A), and recombined in their normal orientations. The arrow below the cells indicates the direction of cell movement by the reference cell. On the right of each panel is the corresponding side view, in which the P₁ isolates are oriented as if looking down from one end, either P₄ or MSxx (as indicated). Yellow arrows indicate the direction of movement of P₄ cells and the green arrows indicate the direction of movement of MSxx cells. Separation and recombination of (A) Ea and Ep, with P₄ as the reference cell; (B) MSxx and Ea, with P₄ as the reference cell; or (C) P₄ and Ep, with MSxx as the reference cell.