Which of the following mechanisms are used to regulate blood pressure in the closed circulatory system of vertebrates?
I.changing the force of heart contraction
II.constricting and relaxing sphincters in the walls of arterioles
III.adjusting the volume of blood contained in the veins
IV.synthesizing new capillaries

Question

Quizplus · Accepted Answer

The closed circulatory system of vertebrates employs several mechanisms to regulate blood pressure. These include changing the force of heart contraction (I), constricting and relaxing sphincters in the walls of arterioles (II), and adjusting the volume of blood contained in the veins (III). Synthesizing new capillaries (IV) is not directly involved in blood pressure regulation in the closed circulatory system of vertebrates. Therefore, the correct choice is D (I, II, and III).

Which of the Following Mechanisms Are Used to Regulate Blood