Answer:The circulatory system is composed of:Heart: The heart is a muscular organ that pumps blood throughout the body. It has four chambers: the right atrium, the right ventricle, the left atrium, and the left ventricle. Blood vessels: Blood vessels are tubes that carry blood throughout the body. There are three main types of blood vessels: arteries, veins, and capillaries. Blood: Blood is a fluid that circulates throughout the body, carrying oxygen, nutrients, and waste products. Blood is composed of red blood cells, white blood cells, platelets, and plasma.