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| Permanent Tissues (Mature Tissues) |
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| The permanent tissues are formed by the differentiated cells, which become specialised to perform specific functions like protection, support, storage and conduction. The permanent tissues always differentiate from the meristematic cells, during the process of growth. |
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| The cells which form the permanent tissues, exhibit the following characteristic features: |
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 The cells vary in size and shape considerably. They may be spherical or oval or polygonal or irregular in shape. Sometimes the cells may also be elongated. |
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 The cells may be either compactly arranged, without any intercellular spaces or loosely arranged with intercellular spaces. |
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 The cell wall may be either thin or thick. Thin-walled cells contain only cellulose in their cell wall. Thick-walled cells contain other compounds like hemicellulose or pectin, in addition to cellulose. In some cases, a rigid polysaccharide called lignin may be deposited in the cell wall. |
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 Cytoplasm in these cells in almost always granular. It is usually found surrounding the vacuole. In highly specialised cells, cytoplasm is absent. |
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 Nucleus may be present or absent at maturity. |
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 Cell organelles like plastids, Golgi complex etc., when present, are in a highly functional state. In highly specialised cells such cell organelles are absent. |
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 Every cell has either one or two large and prominent vacuoles. In highly specialised cells, the vacuole is represented by a space in the cell called lumen. |
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 Ergastic substances are almost always present in the form of secretory products or storage products or excretory products. |
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 Mitotic divisions occur only in less specialised cells. |
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| The permanent tissues can broadly be distinguished into two types, namely |
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 Simple permanent tissues where, the constituent cells are similar in their structure. |
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 Complex permanent tissues where, the constituent cells are dissimilar in their structure. |
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