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At that time, the elaters uncoil to extend out from the spore and will catch air currents. The fact that they are extended only when conditions are dry means that successful spore dispersal is more likely. The mature strobili of a horsetail (Equisetum arvense). A cross section through a horsetail strobilus, showing spores with elaters.
Thus bryophytes disperse by a combination of swimming sperm and usually wind-dispersed spores, in a manner similar to lycophytes, ferns and other cryptogams. The sporophyte develops differently in the three groups.
Mammals contribute to bryophyte and fern spore dispersal by carrying spores on their fur. Small mammals acting as dispersal vectors may have advantages for the dispersing organism compared to wind transport, as the mammals share similar ecosystems to the parent plant, while wind transport is random. Additionally, mammals can transport spores ...
7 Sporangium dehiscence in bryophytes. ... Explosive dehiscence is a ballistic form of dispersal that flings seeds or spores far from the parent plant.
Hornwort spores are relatively large for bryophytes, measuring between 30 and 80 μm in diameter or more. The spores are polar, usually with a distinctive Y-shaped tri-radiate ridge on the proximal surface, and with a distal surface ornamented with bumps or spines.
Spore-bearing capsules or sporangia of mosses are borne singly on long, unbranched stems, thereby distinguishing them from the polysporangiophytes, which include all vascular plants. The spore-producing sporophytes (i.e. the diploid multicellular generation) are short-lived and usually capable of photosynthesis, but are dependent on the ...
In leptosporangiate ferns, the annulus located on the outer rim of the sporangium and serves in spore dispersal. It consists typically of a ring or belt of dead water-filled cells with differentially thickened cell walls that stretches about two-thirds around each sporangium in leptosporangiate ferns. The thinner walls on the outside allow ...
Dispersal is also used to describe the movement of propagules such as seeds and spores. Technically, dispersal is defined as any movement that has the potential to lead to gene flow. [1] The act of dispersal involves three phases: departure, transfer, and settlement. There are different fitness costs and benefits associated with each of these ...