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BIOLOGY AND HUMAN LIFE 



MULTIPLICATION IN PLANTS 



I. Cell division 



In one-celled plants 



Multiplication of individuals 

 In many-celled plants 



Growth of tissues 



Development 



Repair of breaks etc. 



Propagation 

 From root 

 From stem 

 From leaf 



Grafting 



Depends on cell division in cambium layers 

 Parts of graft Kinds of graft 



Stock Twig 



Scion Bud 



Bridge 

 Use of grafts 



Multiply one variety of plant product at expense of another 

 Budding 



4- 



5. Flowers as reproductive structures 

 Stamen (pollen-bearing organ) 



Pollen, spore leading to formation of male gamete 

 Carpel (ovule-bearing organ) 



Embryo sac, spore leading to formation of female gamete 



