Question

The graph given below shows the variation in the levels of ovarian hormones during various phases of menstrual cycle:

(a) Identify ‘A’ and ‘B’. 

(b) Specify the source of the hormone marked in the diagram. 

(c) Reason out why A peaks before B. 

(d) Compare the role of A and B.

Answer 1

(a) 

A – Estrogen 

B – Progesterone 

(b) 

A – Maturing ovarian follicle/Graafian follicle 

B – Corpus luteum 

(c) Formation of Graaffian follicle (releases estrogen) is followed by the formation of corpus luteum (releases progesterone) 

(d) Role of A (Estrogen): leads to changes in the ovary and uterus / regeneration of endometrium through proliferation Role of B (Progesterone): Maintenance of endometrium for implantation of the fertilized ovum/maintenance of other events of pregnancy