AN INTRODUCTION TO THE METAZOA 



C. A simple Protozoon (Plasmodium) . 



CELL DIVISION CELL DIVISION PERMANENT CON- CELL DIVISION CELL DIVISION 



(Schizogany) (Gametogenesis) JUGATION (Sporogany) (Schizogany) 



A sporozoite (sz) Certain merozoites (Fertilization) A zygote gives A sporozoite 



produces many divide, forming one A female cell (egg) rise to many produces many 



merozoites (mz). egg (e} and one polar fuses with a male sporozoites(sz). merozoites (mz). 

 body (pb)\ others give cell (sperm} pro- 

 rise by division to as ducing a zygote 

 many as eight sper- (a), 

 matozoa (s/>). 



D. A simple colony of cells (Pandorina). 



CELL DIVISION CLLL DIVISION CELL DIVISION CELL DIVISION PERMANENT CELL DIVISION 



(Swarm spore (Colony for- (Colony for- (Gamete for- CONJUGATION ( Swarm spore 



formation) mation) mation) mation) The gametes formation) 



Zygote gives Each swarm Each cell of the Each cell of the unite in pairs, Zygote gives 



rise to from i spore produces colony pro- 



to 3 swarm a new colony, duces a new 



spores. colony. 



colony pro- 

 duces a colony 

 of gametes 

 which separate 

 from one 

 another. 



forming rise to i to 3 

 zygotes. swarm spores. 



