protonema 的定义
plural pro·to·ne·ma·ta [proh-tuh-nee-muh-tuh]. /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.
更多protonema例句
- Erect branches may arise from the protonema, and gemmae may be developed on it.
- In mosses (fig. 12) a filamentous growth, the protonema, is first formed, and the leafy plants arise upon this.
- Usually the protonema is filamentous and ceases to be evident after the plants have developed.
- The protonema forms a flat, lobed, thalloid structure attached to the soil by rhizoids, and the plants arise from marginal cells.
- The spore on germination forms a short filament which soon broadens out into the thalloid protonema.