The relation between the rod-like inner structures and the shapes of the cells

The shapes of the cells with simple rod-like inner structures are studied theoretically. Since the cell with inner structure can be bent, the possibility of non-axisymmetric shapes is considered. The equilibrium shape of the cell, obtained by minimizing the sum of the membrane bending energy and the bending energy of the rod, depends on the ratio between the bending constant of the membrane and the bending rigidity of the polymer rod. The dependence of the cell shape on the length of the rod and on the difference between inner and outer membrane layer areas is presented.