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The complex, semifluid, translucent substance that constitutes the interior matter of a living cell and is composed of proteins, fats, and other molecules suspended in water. It includes the cytoplasm, the nucleus in eukaryotes, and organelles such as mitochondria.

pro′to·plas′mic (-plăz′mĭk), pro′to·plas′mal (-plăz′məl), pro′to·plas·mat′ic (-plăz-măt′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
In electron microscopy imagery one could see: a central protoplasmatic cylinder, a cell membrane (three-layered), an outer membrane (envelope), an axial filament with several fibrils, the envelope being covered by a slime layer.
Volume of stressed bull spermatozoa and protoplasmatic droplets, and the relationship of cell size to motility and fertility.