A protonema (plural: protonemata) is a thread-like chain of cells that forms the earliest stage of development of the gametophyte (the haploid phase) in the life cycle of mosses.

The protonema, which grows directly from the germinating spore, is in most mosses an extensive, branched system of multicellular filaments that are rich in chlorophyll. This stage initiates the accumulation of hormones that influence the further growth of newly formed cells.

The protonema is formed from a spore and is a haploid, autonomous, gametophytic stage of the moss life cycle. The primary protonema is responsible for only the germination of spores, while the secondary protonema is responsible for the overall …

The meaning of PROTONEMA is the primary usually filamentous thalloid stage of the gametophyte in mosses and in some liverworts comparable to the prothallus in ferns.

Protonema, the first tissue to emerge from the spore, is a filamentous tissue composed of two main cell types, chloronemal and caulonemal cells (Figure 1). Rhizoids develop from epidermal cells on the gametophore, the P. patens shoot ( Figure 1 ).

The protonema and prothallus are structures seen in primitive plants. The key difference between both these structures is that protonema constitutes the first stage of development in liverworts and mosses, while prothallus is seen in pteridophytes and is its gametophyte.

Sep 16, 2017 · The main difference between protonema and prothallus is that protonema is the first stage of development of mosses and liverworts whereas prothallus is the gametophyte of pteridophytes. Protonema is a thread-like chain of cells whereas prothallus is …

Protonema is a filamentous stage in the life cycle of mosses that develops from the germination of a moss spore. This initial structure plays a crucial role in establishing the gametophyte, which is the dominant life stage in bryophytes.

A protonema is a thread-like chain of cells that forms the gametophyte's earliest stage of growth in the life cycle of mosses. When a moss grows from a spore, it begins as a germ tube that lengthens and branches into a filamentous complex called a protonema, which develops into a leafy gametophore, the adult form of a gametophyte in bryophytes.

Protonema: In bryophytes such as mosses, the gametophyte has three stages of development namely, the spore, protonema, and the leafy gametophore. The spore germinates to form multicellular, branched, and chlorophyll-rich filaments called protonema.