The cardiovascular system comprises two circulatory paths: pulmonary and systemic circulation, which transport deoxygenated and oxygenated blood, respectively. In pulmonary circulation, deoxygenated blood travels from the heart to the lungs for gas exchange, while systemic circulation distributes oxygenated blood from the heart to the rest of the body. Blood moves from the right atrium to the right ventricle, then to the lungs and back to the left atrium, before being pumped throughout the body.