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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.