The Plant tissues Are groups of cells found in plants and interact to achieve a common function.
Like animals, plants are also multicellular organisms. The main plant tissues are found in the root, stem and leaves. They may have different structures and be located in a dispersed or aggregated way.
Plant tissues can be divided into merismatic tissues or permanent tissues. Meristematic tissues are those in which the cells divide and multiply constantly. In permanent tissues the cells do not grow or divide.
Depending on the type of cells by which they are constituted, the permanent tissues can be differentiated into simple tissues and complex tissues. The simple tissues are those that are formed by a single type of cells. In contrast, tissues composed of different cell types are complex tissues.
Also, the main tissue systems that we can find within a plant organism are, the fundamental system, the vascular system and the epidermal system.
Main Tissue Systems
1- Fundamental system
The fundamental system of plants is responsible for the photosynthesis And storage of nutrients. In the same way, this system is responsible for the regeneration of possible tissue breaks and protection against external agents. It stands out for being in charge of supporting the structure of the plant.
In the fundamental system of plant organisms, clusters of simpler tissues can be found, such as the parenchyma, colenchyma, and sclerenchyma.
Parenchyma
Parenchyma is the most common tissue within a plant organism. It can perform various functions depending on the part of the plant in which it is located. The main functions it performs are photosynthesis and storage of nutrients.
It should be noted that within the types of parenchyma found in a plant organism is the chlorenchyme. The chlorenchyma is the main tissue of a plant, since it is where the chlorophyll is to carry out photosynthesis. Without chlorenchyme, no plant can survive.
Colénquima
Colenchyma is another of the fundamental tissues within plant organisms. This tissue is composed of cells with active and active protoplast. Protoplasts are cells that lose their cell wall.
The colenchyma is the main tissue that holds the organs of a vegetable. It is also the main tissue that confers the characteristic flexibility of plants. Just as it is in charge of keeping the leaves in place preventing them from falling
Sclerenchyma
This tissue is formed by dead cells of adult plant organisms that have already stopped growing. The walls of these cells thicken giving greater resistance. There are two types of sclerenchyma cells, fibers and sclereids.
The fibers are cells impregnated with lignin, which is an organic polymer that forms the structures of plant tissues, to a greater or lesser extent. Cells with less lignin and higher concentration of cellulose are those used to make fabrics such as flax or hemp.
Sclereids are cells with higher concentration of lignin. They harden the fabrics and form hard layers, for example almond shells or nuts.
2. Vascular system
The vascular system, as in other living organisms, is responsible for transporting food and nutrients throughout the plant body. They are the most complex tissues that we find within the plant structure. Formed by tubular cells, these can become fused and create conductive tubes.
There are two types of vascular tissue; Xylem, also known as woody tissue; And the phloem or Liberian tissue.
Xylem
It is the main driver of the Raw sap From the roots to the leaves. Crude sap is an aqueous solution of mineral salts. The cells of the xylem, are dead cells, which also converts them into plant tissue.
Within the xylem are the tracheas, which are cylindrical cells that join and form tubes that favor rapid circulation.
Floema
Also known as Liberian tissue, it is in charge of transporting the sap made from the leaves to the rest of parts of the plant body. This tissue is formed by sieve cells, which have no nucleus.
By the end of autumn, the porous walls of the sieve cells are clogged with a substance known as the callus. This prevents the processed sap from reaching certain parts of the plant body. Once spring arrives, this substance dissolves allowing the passage of nutrients to the rest of the plant.
Epidermal system
The epidermal system is in charge of protection. But its most important function is to prevent the loss of water from the body. These tissues are those found in the most superficial part of the plant organism.
Within the epidermal system can differentiate between epidermis and endodermis.
Epidermis
The epidermis is the plant tissue that covers the leaves, stem and root. The cells that form the epidermis do not contain chlorophyll, but are monocells with a large central vacuole.
Vacuoles are water deposits that are found inside the cells. This fabric is covered by the cuticle, which is a wax that facilitates waterproofing.
The epidermis is responsible for the regulation of transpiration and the exchange of gases through the stomata. In the epidermis are also the trichomes, which are appendages that help protect the plant in the form of hairs or becoming thorns.
Endodermis
The endodermis is the tissue of cells that we find in the root of the vegetal bodies. The cells that make up the endodermis have a membrane that allows the passage of water to the plant system to enter the vascular tissue and transport it to the parts containing chlorophyll.
The suberin is the substance that covers the membrane of the endodermis to permeabilizarla and to filter how much of water passes to the vascular tissue.
References
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