Plains (plaunis plants) classes, meaning and life cycle, reproduction and representatives

Plaunovic plants, or plans, are the most ancient group of fernsshaped (they reach giant sizes often about 40 m) and for a long time these plants occupy a dominant position in the open spaces of the entire vegetation cover of the planet.

As a rule, these are evergreens of a perennial type that are strictly protected in law, since they are an endangered look.

Classes of plaunid plants

To date, plainlike plants are a fading group of plants. But, despite this, they can be found on the territory of almost any place on the planet, which is associated with extreme unpretentiousness to any factors of the surrounding space of the plans and with their ability to exist anywhere in the earth.

Modern plainlike are grassy organisms, which are customary to attribute many groups of plants: the total number of plans is about a thousand species. It is the plainlike plants that are considered the first vascular organisms: this is due to the presence of, in addition to perfectly formed deciduous shoots, a real root system.

It is customary to distinguish several classes inside the plaunid department:

Halfwing

These plants are able to exist under water and this ability is characteristic exclusively for this type of this category; or they are habitually in a state of partial immersion in the aquatic environment. According to its external signs, this class is more like cereals, but nevertheless, the seminickels have nothing to do with this detachment.

The halfwire lake

Selaginella

There are almost seven hundred species of these plants, and the habitat has chosen the tropical zone and subtropics (mainly). In appearance, these plants resemble mossy, which is facilitated by the presence of small foliage. Among the total number of Selaginell, you can find species characterized by the presence of only vertical shoots but, nevertheless, they are creeping.

This genus is included in the classroom class, and its adult plants have some similar features with plans, but still there is a sufficient number of distinguishing features.

Plain

This species is the most common and has all the features and features characteristic of all plainlike ones, which is expressed both in external qualities and in the territories of existence. It is they who are considered to be the most important representatives of the plain.

This class of higher plants is precisely spore, which, first of all, multiply with the help of a dispute. This means the absence of seeds or fruits and this fact extremely complicates the process of their artificial formation.

In general, all classes and types of plainlike have many similar features and qualities, and does not compose problems from plants of any other species, especially if you understand the general features and features of the appearance of these plants.

It is customary to divide the plainlike ones into several orders of magnitude:

  • Asteroxil, which consist of extinct species: asteroxilon (a herbaceous plant, which gave rise to all the highest species of lycophiles), and the cheesopodium.
  • Plain, to which it is customary to attribute several genera of plants Plaun and Philloglossum.
  • This clan includes almost four hundred species, many of which are common throughout the neighboring abroad such as a pilateral plan.

  • Protolepidodendro, which includes disappeared plants.
  • Structure

    The characteristics of the structure of plaunum plants, especially their external properties, are fully dependent on the territory of the growth and existence. Historical studies will suggest that the plans are originating from ancient riniophytes, and this is due to the fact that their appearance significantly resembles mossy plants.

    The plans usually have a stem steaming on the ground, rising, or a stem growing directly, but based on a more persistent support or other plants. Typically, the shoots can be observed from the creeping stems, humiliated by small leaves, and in the lower part there are subordinate roots. The stem of this plant has a thin shell, on the outer layer of which the supporting fabric is located, and directly in the middle of the stem, conductive fabrics act.

    The structure of the plainshaped

    Quite often, among the plans, you can find specimens with a small and simple foliage device, but sometimes there are those that are equipped with scaly and needleshaped systems of external organs.

    For example, the same Plaun Bulavoid has a creeping shape of the stem to be up to three meters. Typically, the stem (as well as branches) is equipped with small leaves and it is this characteristic feature that makes the plans similar to mosses. Quite often this plant resembles miniature twigs of a Christmas tree.

    The subordinate roots that are formed on the aboveground shoots of the plaunum plants provide another distinctive feature of this department: many plans are endowed with the ability, clinging to these processes, to move around the trees up.

    In some species of plaunum plants, you can also find tiny branches equipped with one or more leaflets these branches are layouts from the kidneys and provide the process of vegetative propagation of the plant.

    Almost all plainlike plants are characterized by such a property as microphilia, which consists in the small characteristics of the foliage: all the leaves of the plans are formed as superficial outgrowths located on axial organs. This feature endows a group of plain unique uniqueness.

    The stem of the plainshaped is developed quite powerfully, the foliage is located on a spiral feature, opposite and mutual. New shoots appear using the capabilities of the apical meristem. Its activity has lost its activity over time, so the plan is significantly limited in its size.

    The roots of plaunum plants

    The body of any of the plaunum plants is divided into two massive parts:

  • the escape,
  • root.
  • In plainshaped, the root system is present exclusively in the form of weak, multiple, branching from the entire area of ​​the stem, which is in contact with the surface of the soil, hairy short roots, which are called the side roots.

    This is due to the fact that the germinal spine dries very quickly, and the root system is forced to form due to the roots, which are extending from the underground part of the escape, which, in fact, are subordinate.

    The underground parts of some species of plas are characterized by the formation of a typical rhizome equipped with modified foliage and lateral roots, while other plaunum plants have a risophore (cornosz), which is a special peculiar organ intended for the spiral of roots in a spiral of roots.

    An interesting fact is the moment that the anatomical structure of the root system, depending on the indicator of the level of its deepening, changes, which is primarily associated with the specifics of the existence of the existence.

    Signs and characteristics

    The appearance of all the plainlike ones, first of all, directly depends on the place of their existence and the group to which they belong, although such species of plants can be found almost everywhere on the planet.

    This is due to the fact that the plainlike ones, unlike mocking ones, have significantly developed many types of tissues, from cover to mechanical and conducting, which made it possible to grow not only in pine forests, but also in other, more stringent and harsh climatic conditions.

    The characteristics of this department can be considered on the basis of the most extensive group of these plants plain. This species of plants more than others like mossy plants with its small leaves. But this group is quite extensive, therefore, in addition to the plans, you can also find scaly and needleshaped plants, since this group includes a large number of herbs, and the most diverse.

    The plans are mainly characterized by erect stems (less often creeping or lifting), and they have the ability to crawl into the trees using side air roots. In some species, even small branches can be found, called brood buds used as the only system for vegetative propagation, since it is they who are able to separate from the stem, and, being on the ground, grow there.

    Halpers, plain-like plants, have small basal leaves than they are slightly similar to another species, which have nothing to do with the plans-cereals, and their long dark green leaves are characterized by significant roughness. At the same time, the halfspleen in the event that it grows on land, and not in the aquatic environment (this happens exclusively in the territories that are significantly moistened), forms serious thickets.

    It is interesting that some of the halfspleen have white in color near the very base of the plant and it is sharply replaced by a green tint.

    If we talk about Selaginella, then their stem is quite massive (in some cases creeping), and covered with flat leaves; In the case of a creeping stem, I take place vertical branching shoots that resemble fern-like plants.

    It is interesting that if Selaginella does not get moisture, then such a plant simply flows into a peculiar hibernation and for this it is able to twist into a ball.

    In its appearance, all plainlike ones can be described by the following characteristics:

  • evergreen,
  • mediumsized, simple sheets,
  • Small in size.
  • The plain-like ones in their mass are characterized by lifting or creeping stems and it is precisely because of this property that such a plant significantly resembles moss, especially if we take into account their ability to “crawl” along the trunks of trees.

    Many of the features of various groups of plaunid plants are unable to change the general characteristics inherent in this department, and paying attention to such species, it is necessary to take into account the indicated parameters.

    The value of the plainlike plants

    Plants from the Plaunovical Department appeared on the planet several million years ago as woody species forming huge forests. Modern plainlike are evergreens of herbacetype perennial.

    Plaunovic plants, like all that belong to the green organisms, form organic compounds by the inclusion of the photosynthesis process, releasing oxygen into the atmosphere. These plants are widespread over the entire surface of the planet and take an active part in the process of formation of the soil layer.

    Unfortunately, plans did not receive widespread use in the economic sphere; Their disputes are customary to use in the field of the manufacture of medical devices, as well as as addictions.

    So, as a medicinal plant as a children’s powder and sprinkle for tablets, spores of the plaunum of a pinshaped plain are often used.

    Quite often in medical practice, it is the aboveground part of plants and disputes of the plains. It is interesting that disputes appear closer to the end of summer, and you can start collecting them in the fall, when the shoots themselves already acquire a yellow tint.

    Such a value of the plainshaped occurs due to the presence in their composition of a large number of various acids: myiristine, stearin, linolevo, oleinova and others.

    In pediatrics, this enveloping agent is accepted to be prescribed as a children’s powder as a preventive agent for diaper rash, and its properties allows it to be used as a sprinkle for drugs to prevent gluing.

    The brewed disputes and the green mass of plants are recommended to be used in a pharmacy as antiinflammatory, from the manifestations of cystitis, from stones to the kidney, as a laxative, diuretic and even choleretic drug. At the same time, in order not to damage the plant and its disputes need to be accurately cut off with an exclusively sporebearing organ spikelet.

    You can easily cure wounds and burns from a dispute from a dispute, so it is considered in folk medicine. The Plaun-Baranian allows you to solve the problem with alcohol dependence, if you take it in the complex with the help of a psychologist.

    The beneficial properties of the plainshaped are not limited only to medicine: they are often used for decorative purposes, for example, as a decorative decoration, or for the manufacture of wreaths.

    Disputes of the plaunids are often used in the metallurgical industry for shaped casting, it is usually customary to cover forms for the best separation of cast parts.

    Representatives of plaunum plants

    The following species of plants can be considered characteristic examples of plain plants:

    The plaun is flattened, growing in pine forests, where mono to meet a sufficient number of lichens, as well as in swamps where there is moss. This is a creeping perennial plant, on the stem of which there are twigs with leaves, propagating with underground roots.

    A annual plan that is found in our country in territories covered with fir and spruce plantations. Its long stems are equipped with straight branches and reach lengths up to 25 cm, and on its shoots you can find subordinate roots, as well as spore leaflets, due to the hardness of which the plant also named the plaun, prickly.

    Juniper plaun, which is characterized by an erect stem with a length of up to 25 cm, and its lower part in the form of curved branches forms minor bush forms.

    Life cycle of plaunum plants

    In the life cycle of plainlike plants, the advantage receives an asexual generation, t.e. An adult plant is a sporophytic that prevails over a gametophyte. At the same time, the sexual generation, this very gametophyte, is distinguished by a layered strap and is simply an embryo or a small plate.

    The life cycle of the plainshaped is distinguished by several alternating reproduction options among themselves:

  • sexual using gametophyte or gametes,
  • Such a gametophyte does not differ in large sizes and is the name of the embryo and it instantly dies after performing its function, t.e. The formation of a new sporophyte.

  • Sweet, vegetative, t.e. with the participation of dispute or body parts.
  • You need to understand that the last version of reproduction needs the presence of a drop-liquid environment in the surrounding space, t.e. moisture.

    In plainlike sporangia, they are formed with the help of specialized shoots, called strobil, which are sporebearing and retain spikelets with disputes.

    Habitat

    If we talk about the modern flora of our planet, then you can count not such a significant number of species of plainlike plants, but many millions of years ago they flourished and were represented by trees, herbaceous forms the reason for this was the wet climate of the coal period.

    This department contains only a few dozen species, but they are quite actively represented from the tundra to the subtropical belt, but prefer the habitat to choose the northern hemisphere, but in humid warm climate they reach more significant sizes.

    Herbal representatives of this plant of the plants, the same plaunum is pinnal or flattened, actively spread in coniferous forests in Europe: it has the form of numerous stems, which are quite powerfully covered with leaves, which are simply outer layers of the epidermis.

    Propagation of plaunum plants

    Excluding several species, plainlike plants multiply by vegetative propagation, t.e. disputes. These plants do not have seeds and fruits, which greatly complicates their cultivation in artificial conditions and this contributes to a gradual reduction in their total number.

    Plaunovic plants are capable of multiplying in several ways:

  • asexual, using dispute or by rooting shoots,
  • germ, with the participation of germ cells gametes.
  • With ash propagation at the end of the branching shoots, erect spikelets are formed, which are carriers of the dispute. They arise using modified leaves, on which disputes are formed.

    After ripening, spores are spilled out, and a small plate (literally up to 3 mm) of the plate, called the germs, are formed from them. These gametophytes (t.e. sexual generation) form organs of sexual reproduction, thanks to which female and male germ cells, eggs and spermatozoa are formed.

    And after the process of fertilization from the formed zygote, a sporophyte, called the Sweet generation, from which the future plant grows, begins to form from the formed zygot.

    In the life cycle of plainlike plants, the cycle of asexual generation and asexual development prevails.

    The ripened disputes are dispersed and after a while germinate, forming the sexual generation, or gametophyte, and such a transplant in the form of a small nodule (5 mm) continues its development underground. It is for this reason that it is colorless because it is not saturated with chlorophyll.

    In a significant number of plain-like plants, the embryos are located precisely underground and does not have any specific form due to its small size. Plaunovic (some species) can also develop sexually, t.e. Due to male and female gametophytes.

    In biology, such a diverse is adopted for a special tendency in horsetail and fernlike, and it is especially brightly formed in seed plants.

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