A term for the colorless granular matter of which all living cells consist. In eukaryotes, it comprises a nucleus embedded in the cytoplasm. It sometimes is used to refer to cytoplasm, with protoplasm taken to mean everything in a cell except the cell membrane. The distinction used in this way is a source of disagreement among cell biologists. Protoplasm contains a variety of organelles in contrast to the nucleoplasm that houses nuclear material (e.g., chromosomes) nucleoli. This contrast hold for eukaryotes such as plants and animals, but not for prokaryotes where the contents of a cell are together referred to as the cytoplasm.
See Cell. Chromosome, Cytoplasm, Eukaryote cell (or organism), Germ plasm, Nucleus (of a cell), Organelles, Prokaryote cell (or organism), Proteins