What needs to happen to the protein–drug complex for the drugs to reach the cells where the drug can act?

Question

A) The protein–drug complex must break itself into smaller pieces to enter the capillaries.
B) The binding site on the protein picks up a chemical to make it soluble in the serum.
C) The drug must break away from the protein-binding site and float freely.
D) The drug must be dissolved in the plasma so it can enter the capillaries and then the tissues.

Answer 1

C
Feedback:
Most drugs are bound, to some extent, to proteins in the blood to be carried into circulation. The protein–drug complex is relatively large and cannot enter into capillaries and then into tissues to react. The drug must be freed from the protein's binding site at the tissues. This occurs without the introduction of another chemical or by dissolving in it plasma.