The life cycle of the fern: stages, stages, sequence and description

Ferns appeared on Earth many years ago. In ancient times, it was possible to meet forests from tree ferns. To date, there are very few such large plants. Ferns have become more decorative and roomy. They are beautiful and unpretentious, they can be used for landscape design. Plants are durable and interesting.

Legends of the fern

Fern is an unusual plant. With its appearance, a great many beautiful legends are connected. According to one of them, the plant originated from the goddess of love - Venus, who once dropped her hair, from which the fern grew.

The most famous legend is the legend of the fern blooming. It says that if a flower of a plant is seen on the night of Ivan Kupala, the person will discover the secret of how to find treasures. However, when studying it, it becomes clear that the legend can not be embodied in reality, because the life cycle of the fern does not have a flowering stage.

Higher and lower groups of plants

Plants are divided into higher and lower groups. They differ among themselves in their habitats. Higher plants "came out" on land and spend their life cycle on earth. Such plants include ferns. Earth plants have a clear division into the root, stem and leaf.

However, it is impossible to say unequivocally that the ferns have completely moved away from the aquatic habitat, since the free-living gametophyte participates in their reproduction process and the spermatozoa necessary for the fertilization process can exist only in the aquatic environment.

Appearance

Representatives of the detachment of ferns spread throughout the world. They have a different appearance of leaves, environmentally unpretentious, while they love moist soils more.

The fern has a root system, a stem and leaves. He has no seeds. On the inside of the sheet, below, there are spores in the sporangium pouches. The leaves of the fern are called "vayi", they do not look like the leaves of other plants. They look as if several twigs were placed in one plane and attached to the stem. Their color can vary from light green to dark green.

Fern, not counting the root system, consists of vayi, sarusa and indusia, where the sarus is a bundle of sporangia, india - an outgrowth resembling an umbrella that closes the sarus.

Life cycle of higher plants

Existing on the Earth, each plant goes its way. The life cycle of the fern is a movement from the birth of life to the full maturation of the plant, capable of giving a new life. The cycle consists of two phases: asexual and sexual. These phases determine the sequence of generations, one occurs with the help of gamete - sex, the second - with the help of spores - asexual.

Fusing, gametes form a diploid zygote, which gives rise to a new generation, an asexual. In the asexual generation, reproduction occurs with the help of spores. Haploid spores give rise to the sex generation. One of the generations always prevails over the other and makes up most of the plant's life cycle.

Stages of the life cycle of the fern

For the emergence of a new young sprout, several stages are needed. The life cycle of the fern is the totality of all phases, beginning with the birth of life and ending with the phase of maturity, when the plant is already capable of giving rise to a new life. The cycle has a closed character.

The stages of the life cycle of the fern are arranged in the following sequence:

• Spore.
• The gametophyte (the adolescent).
• Egg cells, spermatozoa.
• Zygote.
• The embryo.
• Young plant.

When all stages are completed, the young plant, having developed and strengthened, will be able to repeat this cycle for the birth of the next generation.

Sexless and sexual stages in the process of reproduction

Fern is the result of an asexual generation. Consider the sequence of the life cycle of the fern.

In order to start a new life, adult plants should have spore bags on the back of the leaf, in which maturation of the spores will take place. When the spores are ripe, the bag will burst and spores will come out of it. Under the influence of the wind, they will spread in different directions and, if hit on favorable soil, will germinate. This stage is very important, because without it the plant could not exist. As a result, there will appear an outgrowth - a gametophyte - a sexual generation of the fern. Its shape is like a heart. This heart has from below thin threads - rhizoids, which also attaches to the soil. The fern is bisexual, with small sacs on it: in some, oocytes mature, in others - spermatozoa. Fertilization occurs with the help of water.

Since the seedling is very small and has such a peculiar shape, it contributes to the slow drainage of rainwater and its retention at the bottom. Due to this spermatozoa can swim to the eggs and fertilize them. As a result, a new cell appears - the zygote, from which the sporophyte is formed - the result of a new asexual generation. This embryo consists of a Haustorium, which in its appearance resembles a leg that grows into an adenoid, and at first consumes from it the substances necessary for its growth. After a while, the first leaf of the embryo appears, which is the beginning of fern development.

Thus, in the life cycle of the fern the asexual generation predominates, which gives life to a new large and long-lived plant, and the sex generation is small and rapidly dying. In this case, it is necessary for fertilization.

Reproduction of fern at home

Ferns are interesting and original plants. Therefore, they are often engaged in breeding at home. To the life cycle of the fern passed completely and a new young plant, it is necessary to germinate the spore. A leaf of an adult fern, on which sacks with spores appeared - brown tubercles, are cut off and placed in a paper bag. This package is kept one day in a warm place, periodically shaking.

While the spores ripen and drop out, prepare the mixture for planting. Take a steamed mixture of peat, greens, sand, also add there crushed charcoal, all this is taken in equal proportions. The prepared mixture is placed in shallow pots, pressed and moistened.

Ripe and fallen spores are removed from the package and poured onto the prepared surface. For their germination, favorable conditions are created:

• Temperature regime: optimally 25 degrees Celsius.
• Maintain high humidity.
• Cover the pots with glass.

Poured pots from the spray. When the sprout appears, watering is given special attention, since the subsequent development of the plant is possible only if there is an aqueous medium in which the egg will fertilize.

As soon as the first leaves appear, the glass is removed. Then they are given a little time to adapt to the environment and dive into cuvettes. When the leaves begin to grow up a bit, they first stand in cold hotbeds, and then they are planted in separate pots. Thus, new young plants are obtained, ready to grow and develop further.

Schematically presented life cycle

During its propagation, the plant passes through several stages. For the sake of clarity and better memorization, it is recommended that the issue be sketched. Consider the existing life cycle of the fern, the scheme of which is presented below:

1. An adult plant capable of giving new life.

2. Spores appear on the leaves of the fern.

3. Ripen bags with spores.

4. The bag bursts, the spores drop out.

5. In a favorable ground, the dispute is strengthened and germinates.

6. An adult is formed, which is attached to the ground with the help of filaments-rhizoids.

7. On the embryo there are female and male cells: archegonia and antheridium:

• Female genitalia contain an egg.
• Male genital organs contain spermatozoa.
• Fertilization is possible only in a drop of rain.
• Spermatozoa swim to the ovules and penetrate inside, fertilization takes place.

8. A fertilized egg appears - a zygote. From the zygote, a sporophyte is formed - a young leaf.

9. A new young plant begins its development.

The diagram clearly shows the closure of the life cycle.

Economic importance

The role of ferns in human life is not too great. Different forms of nephrolepis are common indoor ornamental plants. Vayi of some shields are widely used as a green component of floral compositions. The trunks of treelike ferns serve as building materials in the tropics, and in Hawaii their starchy core is used for food.

Conclusion

So, we studied the life cycle of a given plant. You became aware, for example, at what stage of the life cycle ferns appear in the ferns. These are moisture-loving plants, without water their reproduction is impossible. They spread all over the world, while for their lives choose places with high humidity.

In total there are about 10 thousand species of ferns. They are medicinal, decorative, room.

When a new young plant is born, the life cycle begins, which includes the sex and sexless generation. The sex generation is an adolescent, it is very small and does not live long, and the young, strong, long-living plant that appears is a sexless generation. In the life cycle of the fern, the sporophyte phase predominates.

Thus, the main fern generation is asexual, while it is impossible to reproduce without passing the sex generation.