Inactivation of a cell-surface receptor depends on:
A)the binding affinity of the receptor.
B)the activity of phosphatases in the cytosol.
C)the concentration of ligand surrounding the cell.
D)both the binding affinity of the receptor and concentration of ligand surrounding the cell.

Question

Quizplus · Accepted Answer

Inactivation of a cell-surface receptor depends on both the binding affinity of the receptor and the concentration of ligand surrounding the cell. If the binding affinity is high, the receptor may remain occupied for a longer period of time, but if the concentration of ligand is low, it may take longer for the receptor to become completely inactivated. Conversely, if the binding affinity is low, the receptor may quickly release the ligand, but if the concentration of ligand is high, it may take longer for the receptor to become free. Therefore, both factors are important in determining the duration and extent of receptor activation. The activity of phosphatases in the cytosol may affect downstream signaling pathways but does not directly influence receptor inactivation.

Inactivation of a Cell-Surface Receptor Depends On