Possible means of swimming of red algae spores

This article proposes a model for swimming of red algae spores. The model considers a released spore in unbound water as a spherical particle enclosing a liquid incompressible cytosol, in which oscillates a solid spherical organelle. An analysis of the solutions of the Navier-Stokes equations for the cytosol flow caused by the organelle motion within the cell is presented in the limit of small Reynolds number. It is shown that in the case when the cytosol has Newtonian or Maxwell properties, the spore may swim only when the forward and backward trajectories of the organelle are different. In the case of the shear thinning cytosol properties the spore may swim also when the organelle trajectories are the same, but the velocities of forward and backward movements of the organelle should differ. Such a cell may swim in a straight line. The swimming of the model spores completely satisfies experimental data.