What jobs do the circulatory system and the respiratory system do for the human body?

The circulatory system is responsible for transporting blood, nutrients, hormones, and oxygen to cells throughout the body while also removing waste products like carbon dioxide. The respiratory system facilitates the exchange of gases, primarily oxygen and carbon dioxide, by bringing oxygen into the lungs and expelling carbon dioxide from the body. Together, these systems ensure that cells receive the necessary oxygen for metabolism and energy production while maintaining homeostasis by regulating blood pH and gas concentrations.