a)Outline the characteristics of the meristematic tissues . (4 marks) b) Describe the types and roles of meristems

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a) Characteristics of meristematic tissue

  • Retain the ability to divide mitotically 
  • Remain undifferentiated 
  • Cells are thin walled ; 
  • Cells with large nucleus ; 
  • Cells with dense cytoplasm; 
  • Cells have high density of mitonchondria;

(4 marks)
b) Describe the types and roles of meristems
i) Apical meristems
  • Found near the root and shoot apex; 
  • They are responsible of increase in length of shoot and root / primary growth ; 
  • At the apex are the zones of cell division; cell elongation ; and cell Differentiation ;
ii) Vascular cambium
  • Found between the xylem and phloem of woody plants; 
  • Cells give rise to secondary  xylem and phloem; 
  • Resulting to increase in girth / Diameter ; 
  • Secondary parenchyma ; is formed between adjacent vascular bundles resulting to secondary growth ;
iii) Cork Cambium
  • Located beneath the Epidermis; 
  • Divides to form secondary cortex ; and corky cells ; ( to the inside and outside respectively
  • Prevents rapturing of the stem and root when vascular cambium increase in girth
iv) Intercally meristem;
  • Found at internodes and base of leaf sheath ; 
  • Responsible for increase in length of leaf and nodes;
(Max 16 points)

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