EXAMPLES | WORD ORIGIN noun, plural pro·to·ne·ma·ta . [proh-t uh- nee-m uh-t uh] /ˌproʊ təˈni mə tə/ . Botany a primary, usually filamentous structure produced by the germination of the spore in mosses and certain related plants, and from which the leafy plant which bears the sexual organs arises as a lateral or terminal shoot. Origin of protonema 1855–60;
Greek prōto- proto-
Related forms pro·to·ne·mal, adjective
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for protonema Historical Examples of protonema
protonema is always a well-marked stage in the life-history.
They often merge insensibly into the green filaments (
protonema) already noticed.
In mosses (fig. 12) a filamentous growth, the
protonema, is first formed, and the leafy plants arise upon this.
protonema is filamentous and ceases to be evident after the plants have developed.
protonema forms a flat, lobed, thalloid structure attached to the soil by rhizoids, and the plants arise from marginal cells. British Dictionary definitions for protonema noun plural -nemata ( -ˈniːmətə) a branched threadlike structure that grows from a moss spore and eventually develops into the moss plant Derived Forms protonemal or protonematal ( ˌprəʊtəˈniːmət, əl -ˈnɛmət), əl adjective Word Origin for protonema
C19: from New Latin, from
proto- + Greek nema thread
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
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Plural protonemata ( prō′tə-nē) ′mə-tə, -nĕm ′ə- The green filamentous or flat, thallus-like structure that grows from the germinated spores of liverworts and mosses and eventually gives rise to a mature gametophyte.
The American Heritage® Science Dictionary
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