Describe the role of the following hormones in the menstrual cycle.

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a)  Luteinising  Hormone  (LH) Produced  by  the  pituitary  gland;  under  the  influence  of  oestrogen  hormone;  cause  the bursting  of  the  Graafian  follicle;  to  release  a  mature  egg/ovum/causes  ovulation;  stimulates the  change/conversion  of  the  Graafian  follicle;  into  the  corpus  luteum;  stimulates  the corpus  luteum;  to  secrete  progesterone  hormone;

 b)  Follicle  Stimulating  Hormone  (FSH) Produced  by  the  anterior  lobe  of  the  pituitary  gland;  it  stimulates  the  maturation  of  the Graafian  follicle  in  the  ovaries;  stimulates  the  ovarian  tissue/wall  to  secrete  oestrogen;

 c)  Oestrogen Brings  about/stimulates  the  healing  and  repair  of  the  uterine  wall;  after  menstruation; stimulates  the  pituitary  gland;  to  secrete  luteinising  hormone;

 d)  Progesterone  Secreted  by  the  corpus  luteum;  it  stimulates  the  thickening  of  the  endometrium/uterine wall;  in  preparation  for  implantation;  inhibits  secretion  of  the  Follicle  Stimulating Hormone;  therefore  preventing  further  development  of  the  Graafian  follicle;

 Max.  20  mks 

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