Up regulation is defined as what?

Up regulation is defined as what?

• A. Increased number of hormone receptors, increases uptake
• B. Decreased number of hormone receptors, decreases uptake
• C. Desensitization after repeated exposure
• D. No change in receptor numbers

Answer: (A)

Up regulation means increasing the number of hormone receptors on a cell, which makes the cell more responsive to the hormone. With more receptors available, more hormone molecules can bind, leading to greater signaling and uptake. This is different from having fewer receptors (which would reduce uptake) or from desensitization after repeated exposure (which lowers responsiveness without necessarily changing receptor numbers). No change in receptor numbers would keep the responsiveness level the same.

Up regulation means increasing the number of hormone receptors on a cell, which makes the cell more responsive to the hormone. With more receptors available, more hormone molecules can bind, leading to greater signaling and uptake. This is different from having fewer receptors (which would reduce uptake) or from desensitization after repeated exposure (which lowers responsiveness without necessarily changing receptor numbers). No change in receptor numbers would keep the responsiveness level the same.