Meristematic tissue and permanent (or non-meristematic) tissue are the two types of tissue systems found in plants. Meristematic tissue is similar to animal stem cells in that it contains undifferentiated cells that continue to proliferate and contribute to the plant’s growth. Plant cells that are no longer actively dividing makeup permanent tissue.
Meristems give rise to cells that swiftly specialise and become permanent tissue. These cells take on specialised functions and lose their ability to divide. Dermal, vascular, and ground tissue are the three main tissue types. All three tissue types are present in each plant organ (roots, stems, and leaves).
Three basic types of plant tissue.
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Dermal tissue:-The plant’s dermal tissue protects and covers it, as well as controlling gas exchange and water absorption (in roots). A waxy cuticle protects the dermal tissue of the stems and leaves against evaporation. Stomata are unique pores in the cuticle that allow gas to pass through. The root epidermis is not covered by a waxy cuticle like the stem and leaves, which would restrict water absorption. Root hairs, which are extensions of root epidermal cells, enhance the root’s surface area, which aids in water and mineral absorption. Trichomes, which are tiny hairlike or spikey outgrowths of epidermal tissue, can be seen on the stem and leaves and aid in herbivore protection.
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Ground tissue:-The ground tissue system is made up of three simple tissues: parenchyma, collenchyma, and sclerenchyma, which are all derived from a ground tissue meristem . Each basic tissue’s cells are given the same name as the tissue in which they are found.
The name parenchyma comes from the Greek word para, indicating its widespread presence throughout the plant. The cortex and pith of stems, the photosynthetic tissue layer within the epidermis of leaves (mesophyll), as examples the cortex of roots, the pulp of fruits, and the endosperm of seeds . The parenchyma is made up of undifferentiated parenchyma cells that are generally simple in nature.
Metabolic activity (such as respiration, digestion, and photosynthesis) takes place in these cells in most plants because, unlike many other types of cells in the plant body, they retain their protoplasts (cytoplasm, nucleus, and cell organelles) that perform these processes.
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Vascular Tissue:-In vascular plants, vascular tissue is a collection of numerous cell types that permits water, minerals, and photosynthetic products to be delivered throughout the plant. Because non-vascular plants, such as algae and moss, lack vascular tissue, they are unable to transfer water and nutrients efficiently. Vascular plants use their vascular tissue to convey water and nutrients to vast heights, allowing them to feed the crowns of hundreds of feet tall trees.
Plants are made up of various cell kinds, each with its own function. Plant tissues can be simple (one type of cell) or complex (many types of cells) (more than one type of cell). Parenchyma, collenchyma, and sclerenchyma are simple plant tissues.
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Parenchyma cell:-Plant parenchyma cells are the most common and least specialised form of plant cell. They usually have a spherical shape and can be found in all plant organs. They make up the mesophyll in leaves, which is where photosynthesis takes place. They produce the cortex in stems and roots, which is responsible for storing carbohydrates and other components required for plant function. Plant support and nutrient transmission in the phloem are also performed by parenchyma cells. When plants grow, the cells that divide and produce new cells are known as parenchyma cells. The parenchyma tissue is made up of parenchyma cells.
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Collenchyma cells:-Collenchyma cells are elongated cells that support the growth of plant organs such as leaves. Their primary cell wall is robust but lignin-free, allowing them to be flexible. Collenchyma cells form a tissue that bears the same name.
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Sclerenchyma cells:-Sclerenchyma cells are thick due to the presence of lignin, a stiff polymer in their cell walls. When they reach maturity, they are mostly dead, and their primary role is to give mechanical support, such as in the stem.
Xylem, phloem, epidermis, and periderm are complex plant tissues:
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Xylem:-The tissue that distributes water and nutrients from the roots to the leaves is known as the xylem. It is made up of specialised parenchyma cells, tube-shaped cells known as vessels and tracheids, which form long tubes for longitudinal transportation and are normally dead at maturity, and ray cells, which convey signals laterally
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Phloem:-The tissue that transports the sugars created during photosynthesis is known as phloem. It is made up of live cells called sieve tube members (tube shaped cells), which assist control the flow of fluids on the sieve tube members, as opposed to xylem.
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Epidermis:-For protection, the epidermis is normally a one-cell layer on the outside of plant tissues, and it secretes a protective layer known as the cuticle. Parenchyma cells, guard cells in the stomata (gas exchange apertures on leaves), trichomes (hairs), root hairs in the roots, and glands are among the cells found here (substance’s production).
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Periderm:-Periderm, or outer bark, is the outermost covering of woody plants. Cork cells and lenticels, which are clusters of parenchyma cells that assist get more oxygen into the stem, make up the structure.
Conclusion
Meristematic tissue and permanent tissue are the two types of tissue systems found in plants. Meristematic tissue is similar to animal stem cells in that it contains undifferentiated cells that continue to proliferate and contribute to the plant’s growth. Each basic tissue’s cells are given the same name as the tissue in which they are found. The cortex and pith of stems, the photosynthetic tissue layer within the epidermis of leaves , as examples the cortex of roots, the pulp of fruits, and the endosperm of seeds. The parenchyma is made up of undifferentiated parenchyma cells that are generally simple in nature.