How a hydrogen fuel cell generates electricity. The following step-by-step explanation describes how a fuel cell generates the electricity used to power the vehicle: 1. Hydrogen is supplied to the anode (negative) side of the fuel cell. 2. Hydrogen molecules activated by the anode catalyst release electrons. 3. The electrons travel from the anode to the cathode (positive) side of the fuel cell, creating an electrical current. 4.
A. A heart murmur is a sound that is created by inadequate blood flow through the heart and its large vessels, for example the aorta. Some are born with a heart murmur and further testing doesn't reveal any significant problem.This is called a physiological murmur.eart murmur Cardiology An auscultatory sound of cardiac or vascular origin, usually caused by an abnormal flow of blood in the heart due to structural defects of the valves or septum; murmurs may be benign or pathological.
A heart murmur is a continuous sound that is audible with a common stethoscope, produced when blood passes through particular areas of the heart. The heart has four chambers, two atria (singular = atrium) and two ventricles separated by a skeleton of cartilage that separates each chamber. Turbulent blood flow within the heart causes abnormal sounds called murmurs. 2  Most murmurs are functional, or physiologic, and are normal. 3  Some murmurs are due to abnormal function of the valves in the heart.