What is a modular sponge kidney?

A modular sponge kidney is a type of kidney found in some invertebrates, most notably in certain marine sponges and freshwater bryozoans. It consists of a series of interconnected channels, chambers, and canals, which are lined with specialized epithelial cells that facilitate the filtration and reabsorption of water and nutrients. The modular design of this type of kidney allows for increased surface area and efficient processing of fluids, enabling these organisms to adapt to their specific environments.