Final answer:
The water and salty medium that surrounds a cell is known as extracellular fluid. It is distinct from the cytoplasm, which includes the cytosol and internal components of the cell and is not considered to be the surrounding medium.
Step-by-step explanation:
The water and salty medium that surrounds a cell is known as extracellular fluid. This fluid baths all of the body's cells except for blood cells, and it comprises a variety of solutes, including ions and nutrients necessary for the cell's survival. Extracellular fluid is distinct from cytoplasm, which refers to all of the cellular material inside the plasma membrane including the semi-solid cytosol, organelles, and various chemicals but excluding the nucleus in a eukaryotic cell.
The cytoplasm consists of everything inside the plasma membrane excluding the nucleus. It contains the jelly-like substance called cytosol which provides the fluid medium for biochemical reactions. However, the cytoplasm is only considered the internal environment of the cell and is therefore different from extracellular fluid, which is located outside the cell membrane in the surrounding environment.