duhgdgFog5404 duhgdgFog5404 25-05-2019 Biology contestada Which of the following is true of vertebrates with four-chambered hearts? There is a partial gas exchange in one chamber of the heart. There is a partial mixing of oxygen-rich and oxygen-poor blood. There is no mixing of oxygen-rich and oxygen-poor blood. There is a complete mixing of oxygen-rich and oxygen-poor blood.