Protoplasm is the gooey stuff that living cells are made of. A cell's protoplasm is colorless and surrounded by a plasma membrane. Sometimes people use protoplasm to mean “formless blob of life.”

There are many elements that make up the protoplasm of a cell, including the nucleus, amino acids, lipids, and ions. Scientists generally use the word protoplasm to mean the cytoplasm plus the nucleus. It was coined in the 1840s by a German scientist, from the Greek roots proto, "first," and plasma, "something molded or formed."

Definitions of protoplasm
  1. noun
    the substance of a living cell (including cytoplasm and nucleus)
    synonyms: living substance
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    cytol, cytoplasm
    the protoplasm of a cell excluding the nucleus; is full of proteins that control cell metabolism
    karyoplasm, nucleoplasm
    the protoplasm that constitutes the nucleus of a cell
    germ plasm, plasm
    the protoplasm of the germ cells that contains chromosomes and genes
    blood platelet, platelet, thrombocyte
    tiny bits of protoplasm found in vertebrate blood; essential for blood clotting
    multinucleate sheet of cytoplasm characteristic of some stages of such organisms as slime molds
    the intact cytoplasmic content of a cell
    the aqueous part of the cytoplasm within which various particles and organelles are suspended
    the outer granule-free layer of cytoplasm
    the inner portion of the cytoplasm of a cell
    ground substance, hyaloplasm
    the clear nongranular portion of the cytoplasm of a cell
    central body, centrosome
    small region of cytoplasm adjacent to the nucleus; contains the centrioles and serves to organize the microtubules
    the cytoplasm of a striated muscle fiber
    a mass of cytoplasm containing several nuclei and enclosed in a membrane but no internal cell boundaries (as in muscle fibers)
    type of:
    the real physical matter of which a person or thing consists
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