Double Circulatory System in Mammals
1. This circulation system is split into two; the pulmonary and the systemic.
2. The pulmonary system involves deoxygenated blood leaving the right side of the heart to the lungs, & oxygenated blood travelling from the pulmonary vein into the left side of the heart.
3. The systemic system involves oxygenated blood from the left side of the heart travelling to the body tissues, and deoxygenated blood returning to the right hand side of the heart.