Tissues
1) Parenchyma and collenchyma are living tissues whereas sclerenchyma is a dead tissue.
2) Epidermis is the outer protective covering of the plant and is usually layered by cuticle.
3) Stomatal pores, present in the epidermis, are essential for transpiration and gaseous exchange.
4) In older plants, many layered cork is seen, made up of dead and compactly arranged cells.
5) Xylem and phloem are important types of complex tissues in plants.
6) Xylem is composed of tracheids, vessels, xylem parenchyma and xylem fibres. It conducts water and minerals from roots to aerial parts of the plant.
7) Phloem consists of sieve tubes, companion cells, phloem fibres and phloem parenchyma. It transports food from leaves and storage organs to all other parts of the plant.
8) Animal tissues are grouped into 4 basic types – epithelial, connective, muscular and nervous tissue.
9) Epithelial tissues are the covering or protective tissues which act as a barrier between the various systems of the body. It rests on a basement membrane and is composed of tightly packed cells.
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