Fluid dynamics can be treated, as a motion of an inviscid fluid as an indivisible media of particles, or as a collective motion of many body system particles. First case leads to Euler equation of hydrodynamics or more complete Navier-Stokes equations. There are two possibilities of dealing with second case, treat each separate particles as an individual one and propose that each particle satisfies Newton's laws of motion rewritten in stochastic form (Langevin dynamics), or treat each particle as a vertex of geometric figure and search for equations of motion of such surfaces. The surfaces shall be called a differentially variational surfaces (DVS). We had proposed equations of motion of moving surfaces in electromagnetic field, on previous annual meeting, and applied it to analyze micelles morphology and size in aqueous media. Analytical solution of simplified DVS equations, displayed all possible shapes of micelles spanning spheroids, lamellas, and cylinders. Now we shall apply the equations to problems related to cell motility and growth factors. For that, we need some simple modeling to make equations tractable and in some cases analytically solvable. First modeling consideration is that, cell membrane is locally spherical when it is mechanically equilibrated with environment and second, it moves freely. Analytical solution of the equations, for the models, shows that trace of the mixed curvature tensor of the cell membrane is, locally, pressure factor divided on membrane tension. The cell can control motility and growth factor, in the direction of less pressure, by modulating membrane tension, or grow in the less pressure direction, by keeping membrane tension locally constant. According to the equations, pressure factors come from symmetry braking in the gradient of electromagnetic tensor and four current, explaining cell polarization in the direction of less pressure.