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Moss leaf under microscope, showing gemmae and a hair point (40x) Moss gametophytes have stems which may be simple or branched and upright (acrocarp) or prostrate (pleurocarp). The early divergent classes Takakiopsida, Sphagnopsida, Andreaeopsida and Andreaeobryopsida either lack stomata or have pseudostomata that do not form pores.
Prothallus (prothallium) of the fern Polypodium vulgare seen under a light microscope.. A prothallus, or prothallium, (from Latin pro = forwards and Greek θαλλος (thallos) = twig) is usually the gametophyte stage in the life of a fern or other pteridophyte.
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. When a moss first grows from a spore , it starts as a germ tube , which lengthens and branches into a filamentous complex known as a protonema , from which a leafy ...
T. muralis gametophyte Tortula muralis forms greyish-green cushions no more than 1 cm (0.39 in) tall, with tongue-shaped leaves possessing acute to rounded leaf apices that approach a point. [ 6 ] The leaf margins are narrowly recurved near their apex, and are distally bordered with two to four thicker rows of cells that bear or lack papillae.
Polytrichum is a genus of mosses — commonly called haircap moss or hair moss — which contains approximately 70 species that have a cosmopolitan distribution. The genus Polytrichum has a number of closely related sporophytic characters. The scientific name is derived from the Ancient Greek words polys, meaning "many", and thrix, meaning "hair".
Like all moss, the haploid gametophyte is the dominant phase of the lifecycle of P. formosum. The moss gametophyte has photosynthetic leaves, a stem, and root-like rhizoids that anchor them to the substrate. [9] Polytrichastrum formosum is a medium to large robust acrocarpous moss, growing in uncrowded, unbranching tufts.
In Bryopsida the leafy moss plant (q. v. "Thallus") is the haploid gametophyte. [3] It grows from its juvenile form, the protonema, under the influence of phytohormones (mainly cytokinins). [3] Whereas the filamentous protonema grows by apical cell division, the gametophyte grows by division of three-faced apical cells. [3]
An archegonium (pl.: archegonia), from the Ancient Greek ἀρχή ("beginning") and γόνος ("offspring"), is a multicellular structure or organ of the gametophyte phase of certain plants, producing and containing the ovum or female gamete. The corresponding male organ is called the antheridium. The archegonium has a long neck canal or ...