Final answer:
The heart is a complex muscle that pumps blood through three divisions of the circulatory system. Its two pumps force blood through the lungs and the rest of the body.
Step-by-step explanation:
The heart is a complex muscle that pumps blood through the three divisions of the circulatory system: the coronary (vessels that serve the heart), pulmonary (heart and lungs), and systemic (systems of the body).
The heart consists of two pumps, with the right side forcing blood through the lungs and the left side causing blood to flow through the rest of the body. The heart's pumping action is essential for the circulation of blood in the body.