In which system is the lysosome predominantly found?

The lysosome is predominantly found in the cellular system, as it is an organelle present in the cells of various tissues throughout an organism's body. Lysosomes serve as the cell's waste disposal system, containing enzymes that break down macromolecules, old cell parts, and microorganisms. This function is critical for cellular maintenance and homeostasis.

Although lysosomes can be involved in processes related to other systems, such as the immune response in the circulatory system or aiding in digestion by breaking down nutrients in the digestive system, they are fundamentally components of the cellular structure. Hence, their primary association is with the cellular system, where they play a vital role in intracellular digestion and recycling of cellular components.