Synchronization of flagella in cellular carpets derived from Volvox carteri

From unicellular ciliates to respiratory epithelium, the existence of cilia carpets on these cell surfaces enable important functions, such as travelling through the earth’s oceans or debris clearing via fluid flow generation respectively. These cilia are not centrally controlled, but rather work collectively by synchronizing their beating cycles and generating metachronal waveforms. Both theoretical and experimental studies of the mechanisms leading to the emergence of these metachronal waves have been done largely independent of boundary conditions, and so in this study we seek to investigate the validity of this assumption as well as observe the effects of different boundary conditions. Colonial alga Volvox carteri are an ideal model organism for this study due to their size and penchant for metachronal waves. We break these spherical colonies into pieces using a homogenizer, and use imaging techniques to observe how changes in the number of cells, shape, and boundary conditions change how the cilia interact and synchronize with each other. The characteristic shape and size of these broken-off pieces will also inform us on residual stresses in the extracellular matrix (ECM) of a volvox colony as it expands over its lifecycle, and contribute to important questions regarding structural integrity and aging as it relates to ECM in general.