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.
If faults occur in the electrical system, the electricity will flow to earth by the shortest and easiest path. The shortest path is through a circuit breaker or fuse, which will break the electrical circuit. The earth wire should help stop electricity passing through your body if you have an electrical accident.