When a person moves from a supine position to a standing position, which of the following compensatory changes occurs?
High-Yield Explanation
When a person moves to a standing position, blood pools in the leg veins, causing decreased venous return to the hea, decreased cardiac output, and decreased aerial pressure. The baroreceptors detect the decrease in aerial pressure, and the vasomotor center is activated to increase sympathetic outflow and decrease parasympathetic outflow. There is an increase in hea rate (resulting in a decreased PR interval), contractility, and total peripheral resistance (TPR). Because both hea rate and contractility are increased, cardiac output will increase toward normal