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.
1 An electric current in a circuit transfers energy from the battery to the circuit components. 2  No current is âused upâ in this process. 3  In most circuits, the moving charged particles are negatively charged electrons that are always present in the wires and other components of the circuit. An electric current in a circuit transfers energy from the battery to the circuit components. 2  No current is âused upâ in this process. 3  In most circuits, the moving charged particles are negatively charged electrons that are always present in the wires and other components of the circuit.