The cytoplasm is all the material within a eukaryotic or prokaryotic cell, enclosed by the cell membrane, including the organelles and excluding the nucleus in eukaryotic cells. The material inside the nucleus of a eukaryotic cell and contained within the nuclear membrane is termed the nucleoplasm. The main components of the cytoplasm are the cytosol, the cell's internal sub-structures, and various cytoplasmic inclusions. The cytoplasm is about 80% water and is usually colorless.