An adult’s heart is about the size of a large orange and weighs a little less than a pound. The heart is in the middle of the chest. It fits snugly between the two lungs. It is held in place by the blood vessels . Circulation: Adult; Adult: Fetus: 1 Through ductus Arteriosus 2 Through lungs 3 Through foramen ovale.
Jul 14, · The Heart: About the size of two adult hands held together, the heart rests near the center of the chest. Thanks to consistent pumping, the heart keeps the circulatory system working at all times. Circulation System: A circulatory system is a system that is mainly made up of various organs. The main organ that forms the circulatory system is the heart. Various organisms have different types.