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permanent tissue - simple tissue - parenchyma , collenchyma , sclerenchyma.

Permanent tissues   This include Parenchyma, collenchyma , sclerenchyma We have elaborated ground tissues here I)Parenchyma – Distinguishing features- 1)They have power of division whenever is necessary. 2)They are living cells. 3) They are thin walled they have primary and secondary walls of cellulose and hemicellulose. 4)This cells are isodimetric (having same size) 5) They are of variable shape like   oval , polygonal, hexagonal. 6)They have intercellular spaces. They are of two types a)chlorenchyma- Parenchyma cells which have chlorophyll pigment in them known as chlorenchyma. b)aerenchyma – parenchyma cells have air spaces known   as aerenchyma. c)prosenchyma- present in pricycle, long and tapering cells. Where are they present? 1)Cortex of root and stem 2)mesophyll of cells (palisade tissue and spongy parenchyma) Function- 1)They are storage cells. 2)Photosynthesis. 3) gives buyoancy   and helps in floating on water ...