What are the two main part of circulatory system?

The two main parts of the circulatory system are the heart and the blood vessels. The heart is a muscular organ that pumps blood through the blood vessels. The blood vessels are a network of tubes that carry blood from the heart to the body's tissues and back to the heart.

The heart is divided into four chambers: the right atrium, the right ventricle, the left atrium, and the left ventricle. The right atrium receives blood from the body's tissues through the superior vena cava and the inferior vena cava. The right ventricle pumps blood to the lungs through the pulmonary artery. The left atrium receives blood from the lungs through the pulmonary veins. The left ventricle pumps blood to the body's tissues through the aorta.

The blood vessels are divided into three types: arteries, capillaries, and veins. Arteries carry blood away from the heart to the body's tissues. Capillaries are small blood vessels that allow oxygen and nutrients to pass from the blood to the body's tissues and carbon dioxide and waste products to pass from the body's tissues to the blood. Veins carry blood back to the heart from the body's tissues.