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.
When electric charges move in a wire, we say that an electric current flows in the wire. It's like the way a current of water flows in a river. For an electric current to flow, we need two things: something to make the electricity flow, such as a battery or power pack. a complete path for the current to flow in. This is called an electric circuit.