Final answer:
The heart is a muscular organ that uses cardiac muscle cells to pump blood through the body's circulatory system. Cardiomyocytes contract rhythmically, propelling blood into the major vessels, while the skeletal muscle pump assists in returning blood to the heart.
Step-by-step explanation:
The heart indeed has muscles; it is a complex, muscular organ responsible for pumping blood throughout the body. The pumping of the heart is carried out by cardiac muscle cells, or cardiomyocytes, that make up the heart muscle. These specialized cells are connected by intercalated disks that allow the electrical signals to travel and cause the heart to contract in a coordinated manner. The cardiac muscle pumps blood through the circulatory system's three main divisions: the coronary, pulmonary, and systemic.
Additionally, there is a mechanism known as the skeletal muscle pump that aids in returning blood to the heart. The contraction of skeletal muscles around veins compresses the blood, assisting its journey back to the heart against gravity, especially from the lower parts of the body.