You have learnt that a characteristic feature of endocrine system is the presence of feed back loops. By this what is meant if hormone A stimulates gland ‘X’ to secrete hormone B, the production of ‘A’ could be modified when the level of B changes in our blood. An example is the relation

between hormones LH and estrogen (E

2 ). An old woman exhibits the 2 in the 2 in the blood. Where is the defect in both these women? Provide

following features. High levels of LH in blood but low levels of E

blood. Another woman exhibits high level of LH in blood and also high

level of E

suitable diagram to support this answer.