Valves of the Heart. The heart functions by pumping blood both to the lungs and to the systems of the body. To prevent blood from flowing backwards or âregurgitatingâ back into the heart, a system of one-way valves are present in the heart.
An electric circuit is a path in which electrons from a voltage or current source flow. Electric current flows in a closed path called an electric circuit. The point where those electrons enter an electrical circuit is called the source of electrons.
Scientists call the path that electricity takes an electric circuit. Electric circuits are used to carry electricity to places where we can use it. At home, at school, in factories or anywhere that relies on electricity. The electricity is carried to where it is needed by wires. Before electricity will flow, however, it must have a complete circuit.