Explain why blood pressure and heart rate differ when measured in a reclining position and in a standing position.

In the reclining position the heart does not function against the gravity to pump blood to the head of the body. The blood pressure remains maintained. The drop in blood pressure occurs when the person stand up. This can be detected through baroreceptors of the carotid arteries which leads to the brain. These receptors stimulate an increase in heart rate so as to maintain the flow of blood to the brain. This will eventually lead to the increase in the blood pressure.