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Above is a diagram of an open circulatory system. An open circulatory system is made up of a heart, vessels, and hemolymph. This diagram shows how the hemolymph, fluid present in most invertebrates that is equivalent to blood, is circulated throughout the body of a grasshopper.
The muscular system is made up of tissues that work with the skeletal system to control movement of the body. Some musclesâlike the ones in your arms and legsâare voluntary, meaning that you decide when to move them. Other muscles, like the ones in your stomach, heart, intestines and other organs, are involuntary.he circulatory system is the body's transport system. It is made up of a group of organs that transport blood throughout the body. The heart pumps the blood and the arteries and veins transport it. Oxygen-rich blood leaves the left side of the heart and enters the biggest artery, called the aorta.