It should have the shape number 2.
The substance A has a region that will bind to the nerve cell Y.
The drug developed that's going to block the substance A, will have to have a region that is complementary to the substance A. If those two regions get linked the substance A will have nowhere else to bind.
The substance A has a region that will bind to the nerve cell Y.
The drug developed that's going to block the substance A, will have to have a region that is complementary to the substance A. If those two regions get linked the substance A will have nowhere else to bind.