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.
Quick rise and fall of the a cell's electrical membrane potential, in oder to make an electric impulse travel; from the moment the impulse enters the neuron through a dendrite to the moment it leaves through the axon to go to another neuron. Chemical Synapse. How does a nerve impulse travel.