The first landmasses that currently grow are mosses. Biology has a separate direction for the study of this group - bryology. Scientists suggest that life arose in water. Over time, algae acquired traits that helped them survive in drought conditions. Further evolution led to the appearance of spore-bearing terrestrial plants.
Characteristic features of the structure
Bryophytes are higher plants. They appear the first plant tissue - a group of specialized cells. This is the main and photosynthetic tissue. Since conductive and mechanical tissues are absent, the body of mosses is represented by a thallus, like algae. However, it has a leaf-stem structure. The function of attachment to the substrate and absorption of water with nutrients is carried out by rhizoids. From real roots, they differ in the absence of tissue.
Bright representatives of this plant group are moss "phoenix", "cuckoo flax", sphagnum, marchanthus.
Life cycle
The bryophytes are capable of reproduction asexually and sexually. Therefore, in their life cycle there is a clear alternation of generations - sexual (gametophyte) and asexual (sporophyte).
Gametophyte moss is a small stalk with leaves on which germ cells develop - gametes. During the fertilization process, the eggs are fertilized by sperm. For this, water is required. That is why mosses always grow in moist areas of the soil. As a result, an embryo forms, which develops into an asexual generation. The sporophyte grows on the gametophyte and is a threadlike dry leg with a box. Inside it are spores - asexual reproduction cells. They spill out of the capsule, germinate, and the leafy gametophyte forms again. It is easy to guess that it is the sexual generation that dominates in the life cycle of mosses . Since everyone is used to what it looks like a green soft carpet.
Moss Classes
The classification of the mossy is based on the difference in the anatomical and morphological features of the structure of these organisms.
Green mosses are unique plants. So, moss "cuckoo flax" is able to absorb water 4 times its own size. Their color is greenish-brown, mainly perennial plants. They grow very quickly, covering any surface with a continuous green carpet - soil, asphalt, roofs. The only condition is the constant presence of moisture. Because without water, these organisms are not able to multiply.
Some of them, for example, moss "phoenix", are able to live in water. This beautiful plant got its name because of its resemblance to the tail of the famous mythological bird Phoenix. It is absolutely unpretentious, survives even in hard water with any light intensity. Since it was imported from America, the optimum temperature of the water is also not fundamental and ranges from 18 to 30 degrees. Moss "phoenix" looks like a beautiful green fountain, "pouring" from the decorative snags of the aquarium.
White or peat mosses are most often found in swamps. The representative of this group of mosses is sphagnum. It has a characteristic structure of leaves, which consist of two types of cells. The former have a typical structure and contain green plastids, chloroplasts that carry out photosynthesis. The second ones are larger, dead, transparent. They are located between the chlorophyll-bearing cells. They are important for the plant. Absorbing a large amount of water, they are able to hold it for a long time in their cavities, if necessary, giving it to living cells. Where sphagnum settles, the soil quickly begins to swamp.
The value of the bryophytes
Green mosses, along with other groups of bryophytes, are powerful accumulators of moisture. Their appearance serves as a serious signal about the beginning of waterlogging of the soil. On the one hand, this process significantly reduces the area of free arable land. On the other hand, it serves as a condition for the formation of peat. This valuable mineral is used as fuel, fertilizer, and raw materials for the chemical industry. Many representatives of this group of plants have a very attractive aesthetic appearance. So, moss "phoenix" is used to design aquariums. Mosses are able to secrete special substances - acids. They can destroy hard rocks, contributing to soil formation.