§ 4 



POTENTIALITIES IN FOLLICLE 

 Atresia 



99 



Pre-ovulation corp. lut. 





epithe/o- 

 tropic 

 factor 



granul. 

 luteinisation 



C.I. 



horm. 



Fig. 71. Genesis and function of (A) the theca-lutein cells; (B) the pre- 

 ovulation-, and (C)post-ovulation corpus luteum. 



a. an anterior pituitary factor stimulates the granulosa, 

 hypertrophy appearing as luteinisation; 



^. 2i thecotrophic factor may either be absent or remain 

 without effect on the blocked-up thcca cell; 



7. granulosa substances (perhaps of an enzymatic nature) 

 cause oolysis; 



d. the granulosa in most cases resorbs the degenerating 

 ovum; only in exceptional cases (Elephantulus type) does 

 this cell remain intact; 



