Final answer:
The correct answer is proteins, which are complex organic molecules that perform a myriad of functions within cells and are not specifically regulated to maintain cell volume.
Step-by-step explanation:
The question is focused on elements within cells that are not closely regulated to maintain cell volume. The correct answer is proteins, which perform many functions in cells. Proteins may act as structural, regulatory, contractile, or protective elements; they can also participate in transport, storage, or be a part of cell membranes, or they can function as toxins or enzymes. As large organic molecules, proteins are polymers of amino acids, arranged in a linear sequence.
Inorganic ions, on the other hand, are smaller and can affect the osmotic balance of the cell, thereby influencing cell volume. Ions contribute to electrical impulses, stabilize protein structures, aid in hormone release, and importantly, help maintain the osmotic balance that controls water movement. Therefore, unlike proteins, the concentration of ions is closely regulated to maintain cell volume.