The cone of stalk growth in plants. Educational fabric

Plants grow throughout life, and this ability dramatically differentiates them from animals. The main role in the formation of new shoots is played by the cone of growth - a special structure, the cells of which are constantly divided. This zone is located on the tops of the kidneys, as well as on the apex of the main stem. How do plants manage to grow constantly?

The cone of growth: what is it and what is its role?

At the tops of the stem and root of the plant is a special fission zone, which is formed by the cells of the meristem. A feature of this plant tissue is the ability for continuous and rapid division, which leads to the growth of the entire body organs in length and thickness.

Educational tissue is also located on the tops of green kidneys. Actually, for this reason, new shoots are emerging from them, which allow the plant to extend over a large area and receive more solar energy for photosynthesis. There are three types of kidneys: apical, lateral and accessory. The first are located on the apex of the plant, and their growth point allows the body to grow in length. The lateral buds are on the trunk and are responsible for branching, that is, the formation of lateral shoots. The prenatal kidneys are considered asleep and activated if the meristem ceased to divide at the apex.

What does the cone of growth consist of? First, it is formed by meristem cells, which quickly divide and subsequently determine all other tissues. Secondly, near the growth zone there is a rudimentary stem, rudimentary leaves and an embryonic kidney, which will form the basis for the formation of a young shoot.

The cone of stem and root growth

The educational tissue concentrates primarily on the tops of the plant, that is, on apex of the stem and on the tip of the root. The stem, thus, like the root, increases its length by dividing the cells of the mesoderm. The latter, in turn, in the process of determination form new types of cells and tissues. In the stem are the conductive tissues (phloem and xylem), the underlying tissue, the integumentary, and so on.

The point of root growth has its own peculiarities. Since it is at the end of the root and responsible for its growth in length, hard soil could quickly destroy the thin walls of cells of the educational tissue, which would stop the fission process. Therefore, over the division zone is located the root cover, the cells of which peel along with the soil, thereby protecting the vulnerable mesoderm cells, and also secrete mucous substances that help advance the tip of the underground organ of the plant.

Meristem - educational tissue of plants

The tissue that makes up the bulk of the cone of growth of the kidneys, stem and root, is called "meristem." This educational tissue consists of small thin-walled cells that have a large nucleus and small numerous vacuoles. The meristem function is the rapid division and increase in plant biomass.

Localization meristems are divided into apical, lateral and intercalary.

• Apical meristems are located on the tops of the stem and root. Their main task is to increase the length of the plant.
• The lateral educational tissue is represented by a ring of cambium in the stem and a pericyzle in the root. In herbaceous plants, this meristem quickly disappears, and in perennial wood it remains, which makes it possible to grow the stem and root in width. As a result of the operation of the lateral meristem, so-called annual rings are formed.

• Interstitial, or intercalary, meristem is in the area of nodes of herbaceous plants. This type of educational tissue is best manifested in the family of cereals, since it is responsible for the growth of internodes in length.

Wound meristems are also distinguished, which are formed at the site of mechanical damage to the body of the plant through the despecialization of nearby tissues (most often parenchyma).

By the time of origin, meristems are divided into primary and secondary. The first form the body of the embryo, and the latter are already observed in the young formed plant.

Use of meristem in practice

Sometimes, domestic or garden plants begin to grow rapidly in length, not at all branched into small side shoots. To avoid excessive growth of the stem in height, resort to cutting off its top. As a result, the cone of growth disappears, and the plant begins to branch actively due to lateral and intercalary kidneys.

If, on the contrary, it is necessary to prolong the growth process in length, it is by no means possible to cut the tip of the stem. This will lead to the loss of the educational tissue, which is responsible for increasing the body of the plant.

Conclusion

The cone of growth plays a key role in the growth of representatives of the flora. It is formed by cells of the meristem, or educational tissue, which creates new apical and lateral shoots. The cone of growth is in the kidneys, which protect the meristem from the effects of the environment. Actually, any kidney gives rise to a new shoot due to division of mesoderm cells.