The primary function of the cardiovascular system is to transport blood, which carries oxygen, nutrients, hormones, and waste products throughout the body. This system, consisting of the heart, blood vessels, and blood, plays a crucial role in maintaining homeostasis by regulating blood pressure, temperature, and pH balance. Additionally, the cardiovascular system is vital for immune function, as it circulates white blood cells to fight infections. A healthy cardiovascular system is essential for overall well-being and longevity.