Chemical Coordination and Regulation Question 71
71. How does steroid hormone influence the cellular activities?
(a) Changing the permeability of the cell membrane.
(b) Binding to DNA and forming a genehormone complex.
(c) Activating cyclic AMP located on the cell membrane.
(d) Using aquaporin channels as second messenger.
Show Answer
Answer : b
Hints & Solutions
(b) Steroid hormones pass through the plasma membrane of a target cell and adhere to intracellular receptors residing in the cytoplasm or in the nucleus. In the nucleus, the hormonereceptor complex binds to a DNA sequence, called a hormone response element, which triggers gene transcription and translation. Intracellular receptors are located in the cytoplasm of the cell and are activated by hydrophobic ligand molecules that can pass through the plasma membrane. Cell-surface receptors bind to an external ligand molecule and convert an extracellular signal into an intracellular signal.
