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INTRODUCTION TO EMBRYOLOGY OF ANGIOSPERMS 



Type 



Megasporogenesis 



Megaspore 

 mother cell 



Division 

 I 



Division 

 II 



Megagametogenesis 



Division 

 III 



Division 

 IV 



Division 

 V 



Mature 

 embryo sac 



Monosporic 



8 -nucleate 



Polygonum type 



Monosporic 



4 -nucleate 



Oenothera type 



Bisporic 

 8 -nucleate 

 Allium type 



Tetrasporic 



16 -nucleate 



Peperomia type 



Tetrasporic 

 16 -nucleate 

 Penaea type 



Tetrasporic 

 16 -nucleate 

 Drusa type 



Tetrasporic 



8 -nucleate 



Fritillaria type 



Tetrasporic 



8 -nucleate 



Plumbagella type 



Tetrasporic 



8 -nucleate 



Plumbago type 



Tetrasporic 

 8 -nucleate 

 Adoxa type 





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Fig. 55. Diagram showing important types of embryo sacs in angiosperms. 



