Question

. Describe how blood flow through the peripheral circulation is regulated during a) Exercise b) Hemorrhage How is the mean arterial pressure restored in each case?

physiology

Answer 1

Exercise and hemorrhage are states of high and low blood flow respectively. In case of exercise, there are two potentially competing physiological needs. This is because metabolic costs of muscle contraction can be high as well as prolonged, blood flow in the skeletal muscle needs to be matched with the metabolic demands of contracting muscle. Regulation of blood pressure should also be accurate to ensure adequate perfusion pressure to all organs. In case of hemorrhage there is acute blood loss. Blood vessel constricts, the blood restricts or can even be decreased. This helps in retaining body heat or increasing vascular resistance. This also makes skin turn pale. It is because less amount of blood is able to reach the skin surface and thus reduces the radiation of heat.