• Mar 1, 2026 biology of amphibians duellman and trueb e a three-chambered heart, comprising: Two atria: Receiving oxygenated and deoxygenated blood. One ventricle: Mixing oxygenated and deoxygenated blood, which is less efficient but sufficient for their metabolic needs. This circulatory setup supports their activity levels and va BY Jaunita Ullrich
