A. The cell model assumes cylindrical symmetry. Points on the cell boundary (*x*∈Γ) are obtained implicitly. B. Using a viscoelastic description of the cell (Equation 3), cell boundary/membrane displacements (*x*_{m}) are generated by moving the potential function (φ, not shown) according to the total stress applied, σ_{tot} (Equation 4). The spring-dashpot (*K*, *D*) elements represent the mostly elastic cortex, which moves a distance *x*_{cor}. The viscous component (*B*) represents the cytosol, which moves a distance *x*_{cyt}. Values for *K*, *B* and *D* were previously obtained using micropipette aspiration experiments and are given in . C. Area density maps (*D*_{r}(*z*) and *D*_{z}(*r*)), obtained by summing the cell area (in the *z-r* plane) one axis at a time (Equation 5). The resultant adhesion map, shown overlaid on the cell shape, is obtained by multiplying these two together. D. Protrusive stress is assume to work in the *z*-direction away from the furrow according to Equation 7, but only the component normal to the boundary is used. E. Geometry of contractile stress. Though myosin II acts radially, its effect is to reduce the circumference, and hence radius. This can be recreated by applying a stress (σ_{myo}) inwards radially (shown in gray).

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