protonema

American  

[proh-tuh-nee-muh] / ˌproʊ təˈni mə /

noun

Botany.

plural

protonemata

1. 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.

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protonema British  

/ ˌprəʊtəˈniːmətəl, -ˈnɛmətəl, ˌprəʊtəˈniːmə /

noun

1. a branched threadlike structure that grows from a moss spore and eventually develops into the moss plant

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protonema Scientific  

/ prō′tə-nē′mə /

plural

protonemata

1. 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.

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Other Word Forms

• protonemal adjective

Etymology

Origin of protonema

1855–60; < New Latin < Greek prōto- proto- + nêma thread

Example Sentences

This tangled mass of green threads, called the protonema, is the first growth, from which the moss stems spring.

From Through Magic Glasses and Other Lectures A Sequel to The Fairyland of Science by Buckley, Arabella B.

Besides this, gemmae may be formed on the protonema, on the leaves or at the apex, and some mosses have specialized shoots for their better protection or distribution.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various

The protonema forms a flat, lobed, thalloid structure attached to the soil by rhizoids, and the plants arise from marginal cells.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various

Vegetative propagation is widely spread in the mosses, and, as mentioned above, a protonema is always formed in the development of the new plant.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various

The protonema is usually filamentous, and in some of the simplest forms is long-lived, while the small plants borne on it serve mainly to protect the sexual organs and sporogonia.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 "Brescia" to "Bulgaria" by Various