Ciliary locomotion in presence of boundaries

Micro-organisms in nature navigate through a variety of fluidic geometries and chemical conditions. We investigate the effect of confined spaces in nature by introducing \textit{Paramecium Multimicronucleatum} in two different configurations: a capillary tube {\&} a wavy PDMS channel. \textit{Paramecium} swims by creating the metachronal waves due to ciliary beating. The influence of the walls on \textit{Paramecia} is characterized by measuring the velocity and observing the ciliary beating pattern. Theoretically, we also model the system by solving the stream-function with a pressure gradient. The theoretical and experimental observations are compared and conclusions are drawn about the change in the swimming characteristics as compared to free swimming without the boundaries.