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TISSUES
A tissue is a group of cells that are similar in structure and work together to perform a particular function in the body. Example: In plants, xylem tissue helps in carrying water; in animals, muscle tissue helps in movement.
Types of Tissues : Two types
1. Plant Tissues :Found in plants.They are of two types:
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Meristematic Tissue – Made of young, actively dividing cells. Helps in growth.
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Apical meristem → at tips, increases length.
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Lateral meristem → at sides, increases thickness.
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Intercalary meristem → at nodes, helps in regrowth.
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Permanent Tissue – Made of mature cells, performs fixed functions.
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Simple permanent tissue → parenchyma, collenchyma, sclerenchyma.
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Complex permanent tissue → xylem (carries water), phloem (carries food).
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2. Animal Tissues: Found in animals.They are of four main types:
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Epithelial Tissue – Covers body surface, protects organs. (e.g., skin lining)
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Connective Tissue – Joins and supports different body parts. (e.g., blood, bone, cartilage)
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Muscular Tissue – Helps in movement by contraction and relaxation. (e.g., muscles of arm, heart)
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Nervous Tissue – Helps in carrying messages between brain and body. (e.g., nerves, brain, spinal cord)
