a. OUTLINE THE CHARACTERISTICS OF THE MERISTEMATIC TISSUES .[4MKS] b. STATE AND DESCRIBE THE TYPES OF MERISTEMS. [16MKS]

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a.      Outline the characteristics of the meristematic tissues .[4mks]
 Characteristics of meristematic tissues
Retain the ability to divide mitotically
Remain undifferentiated
Cells are thin walled  
Cells with large nucleus
Cells with dense cytoplasm
The cells have high density of mitochondria ;

b.      State and describe the types of meristems. [16mks]

            b)i)       Apical meristems;
Found at the root and shoot apex; they are responsible of increase in length of shoot and root i.e. 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 decide to 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 Preventing rapturing of the stem and root when vascular cambium increase in girth.
           
            iv)        Intercalary meristem;

Found at internodes and base of leaf sheath; are responsible for increase in length of leaf and nodes;                                                                   (Max 16 points)

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