Zoology - Chemical Coordination and Integration Question with Solution | TestHub

Parathormone increases the calcium levels in the blood, while calcitonin decreases the calcium levels in the blood; hence, they are antagonistic. Glucagon increases glucose levels in the blood, while insulin decreases glucose levels in the blood; hence, they are antagonistic. Aldosterone increases blood pressure, while ANF decreases blood pressure; hence, they are antagonistic. Both thyroxine and erythropoietin stimulate erythropoiesis, and hence, they are synergistic.