The forest dead of these ferns helped to form the current deposits of coal of coal, some tropical ferns are arborescentes, in changes the majority of ferns of the moderate regions have rizomas horizontal very superficial from which they divide the filiform roots; the rizomas are usually perennial, of a form every year him new frondes erectos grow, there are also some species of aquatic floating ferns.
It shows seizure of the genre Adiantum. (Photo taken and edited for 
Parts of a fern to just as the top plants, it has roots, stems but they do not produce flowers, but an ear of esporangios, according to the species, are plants with textiles vascular for his interior, the function of his small stem, because it extends as a rhizome, they can be air or underground. As for the sheets he is named frondes and they are usually big, an important fact the sheets realize double function: the photosynthesis and the production of reproductive cells.
Reproduction of the ferns.
Mostly according to the zone and region that one finds, is a plant that is located where excess and moisture exist, but in case of the tropical zone they exist the moisture, because the union of his sperm cells always takes place in the water. His reproduction is very complex, when this moment comes, in his organ the esporangios, in which it can be located in the sheets and other in the shape of ear, where thousands of spores originate, the esporangios gather together in mass named soros, often he is protected by the indusio, which is membranes that grow in the sheets or ears.
Reproduction of the ferns of the genre Adiantum. shows seizure of the ear of the esporangios. (Photo taken and edited for
When the spores fall down in humid area, they germinate giving to the prótalos, it gives these to place to a new fern. For this occasion work with a fern of the genre Adiantum, where I took sample of the farming, and also work with the esporangio type comes into ear from this plant and to one of the bag of the esporangio a longitudinal court is realized, where the nucleus is observed, where you find the spores it has, apart this plant has frondes delicate and big beauty, from what great species they are cultivated as plant ornamental. They grow in humid zones and even in submitted areas of a permanent way to the water and the sun, in tropical zones.
The esporangios is the organ that the spores contain, for this way her to throw them on the outside. it shows seizure of the ear of the esporangios and the cocoons of indusio or small esporangios with a longitudinal court, to see his nucleus. (Photo taken and edited for
alternating Cycle of the ferns.
The visible plant, which we know as fern, is the esporófito and he is physically separated from the gametófito, since it has form of smoothed and heart-shaped plate, of scarcely two centimeters long, is of green color and it receives the name of prótalo, this plant they produce big sheets, calls frondes, on which the esporangios develop, to tripes inside a few called structures soros. When they mature the spore, they are liberated and fallen down to the soil, where they develop and lead to a prótalo, in this one the sexual reproduction takes place, with the sperm cells produced by the sexual organs, which grow when the gametófitos reaches the ripeness, the result of the fertilization is a cigoto. To measurements that develop the last one, the prótalo is degenerating to disappear and of the cigoto a new esporófito finishes with going out.
The vital cycle in the ferns are characterized by the stock of two differentiated well generations, a gametófito haploide of tiny size and an esporófito diploide that constitutes the visible plant. Heinrich Braun, Alexander Carl, German botanist who prepared, along with Schimper, the theory of the filotaxia spiral according to which the growth of the stem takes place in spiral up; therefore, the sheets are placed according to geometric fixed rules.
Contribution of the ferns to the science.
• The importance of the ferns has been historically tied to the ambience of the ornamental thing, serving the same one in the title of the florist shop. Also, in some cases, the ferns can be used to cure some complaints and to eliminate certain parasites, also under a meticulous process it serves as fuel as coal of coal, fertilizers.
• Also we have the case of the species, the impregnations of silica, which Equisetum presents in the epidermis, which allows, that is used like abrasive, to polish metals or as scourer, to wash fret.
• As colonizing and forming plants of soils, favoring the establishment of other species in the process of vegetable succession.
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