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arXiv · 1805.07744

Optimal morphometric factors responsible for enhanced gas exchange in fish gills

Prasoon Kumar·Prasanna S Gandhi·Mainak Majumder
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Abstract

Fish gills are one of the most primitive gas/solute exchange organs, having the highest ventilation volume, present in nature. Such performance is attributed to a functional unit of gill - secondary lamella - that can extract oxygen from an ambience even at a very low partial pressure. For centuries, gills have stood as one of the simplest but an elegant gas/solute exchange organs. Although the role of various morphometric factors of fish gills on gas/solute exchange capabilities have been reported, there has been limited understanding on what makes fish gills as an excellent gas/solute exchange system. Therefore, in the current study, we have theoretically studied the variation of few structural and parametric ratios, which were known to have role in gas/solute exchange, with respect to the weight of fishes. Thereafter, modelling and simulation of convection-diffusion transport through a two dimensional model of secondary lamella were carried out to study different factors affecting the performance of gills. The results obtained from both the studies (theoretical and computational) were in good agreement with each other. Thus, our study suggested that fish gills have optimized parametric ratios, at multiple length scales, throughout an evolution to arrive at an organ with enhanced mass transport capabilities. Further, our study also highlighted the role of length of primary and secondary lamella, surface area of secondary lamellae and inter-lamellar distance on gas/solute exchange capabilities of fish gills. Thus, these defined morphological parameters and parametric ratios could be exploited in future to design and develop efficient gas/solute exchange microdevices.

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Prasoon Kumar, Prasanna S Gandhi, Mainak Majumder. 2018-05-20. Optimal morphometric factors responsible for enhanced gas exchange in fish gills. https://arxiv.org/abs/1805.07744

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