  Swimming of microorganisms is studied from a viewpoint of extended objects
(strings and membranes) swimming in the incompressible f luid of low Reynolds
number. The flagellated motion is analyzed in two dimensional fluid, by using
the method developed in the ciliated motion with the Joukowski transformation.
Discussion is given on the conserved charges and the algebra which are
associated with the area (volume)- preserving diffeomorphisms giving the
swimming motion of microorganisms. It is also suggested that the $N$-point
string- and membrane-like amplitudes are useful for studying the collective
swimming motion of microorganisms when fluctuation of the vorticity
distribution exists in the sticky or rubber-like fluid.
