The common term for the fluid found in cells is cytoplasm. This gel-like substance fills the interior of the cell and contains various organelles, enzymes, and nutrients necessary for cellular functions. The cytoplasm plays a critical role in metabolism, as many metabolic processes occur here. Additionally, it facilitates the movement of materials and signals within the cell, and supports its structure. It is essential for maintaining the proper environment for organelles to function effectively and for overall cell health.