1 Electromagnetic coil, formed when a conductor is wound around a core or form to create an inductor or electromagnet.  Ignition coil, an electromagnetic induction coil used in internal combustion engines to create a pulse of high voltage for a spark plug.
systemic circulation the general circulation, carrying oxygenated blood from the left ventricle to the body tissues, and returning venous blood to the right atrium. umbilical circulation fetal circulation through the umbilical vessels. vitelline circulation the circulation through the blood vessels of the yolk sac.
A twisting cord of blood vessels, called the umbilical (um-bilâi-kal) cord, connects the embryo to the placenta. The best intensive care units found in modern hospitals hardly rival the placentaâs life-support capabilities. The yolk sac is another structure vitally important during early development.