Movement by microorganisms in water is very different from that of large animals. This is due to the overwhelming effects of viscosity at small size scales.
A microbe swimming through water is like a human swimming through molasses.
Movement in water requires special techniques. Successful techniques are the ‘flexible oar’ (cilium), the ‘corkscrew’ (forward facing flagellum) and cellular deformation.
View the videos to see these techniques in action.
(All images by Harvey Marchant)