Question

According to the accepted concept of hormone action, if receptor molecules are removed from target organs, then the target organ will

• A. continue to respond to the hormone without any difference
• B. not respond to the hormone
• C. continue to respond to the hormone but will require higher concentration
• D. continue to respond to the hormone but in the opposite way

Answer 1

Answer: (B)

not respond to the hormone

Answer 2

Hormones produce their effects on target tissues by binding to specific proteins called hormone receptors located in the target tissues only. Hormone receptors present on the cell membrane of the target cells are called membrane-bound receptors and the receptors present inside the target cell are called intracellular receptors, mostly nuclear receptors (present in the nucleus). Binding of a hormone to its receptor leads to the formation of a hormone-receptor complex. Each receptor is specific to one hormone only and hence receptors are specific. Hormonereceptor complex formation leads to certain biochemical changes in the target tissue. Target tissue metabolism and hence physiological functions are regulated by hormones. If these receptor molecules are removed then a hormone will be unable to give any response.