protonema

[ proh-tuh-nee-muh ]

noun

, Botany.

, plural pro·to·ne·ma·ta [proh-t, uh, -, nee, -m, uh, -t, uh].

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.

protonema

/ ˌprəʊtəˈniːmətəl; -ˈnɛmətəl; ˌprəʊtəˈniːmə /

noun

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

protonema

/ prō′tə-nē′mə /

, Plural protonemata prō′tə-nē′mə-tə,-nĕm′ə-

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.

Derived Forms

• ˌprotoˈnemal, adjective

Other Words From

• proto·nemal adjective

Word History and Origins

Origin of protonema¹

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

Word History and Origins

Origin of protonema¹

C19: from New Latin, from proto- + Greek nema thread

Example Sentences

When it lands, the spore sprouts a collection of alga-like filaments called a protonema.

From Scientific American

After a few weeks, leaflets begin to sprout from the protonema and grow into the moss plant we know and love.

From Scientific American

When the scientists cultured these stunted but sprouty sporophytes to see what would happen, the filaments grew into a mass resembling a protonema after a week.

From Scientific American

A week after that, the protonema produced a leafy bud resembling that made by normal moss gametophytes.

From Scientific American

C, a normal "wild type" haploid moss gametophyte sprouting from its filamentous protonema.

From Scientific American