re-write this in a shorter paragraph:
The circulatory system of mammals makes a figure-8 pattern through the dual circulation pathway of the body. The circulatory system in mammals consists of two main components: the systemic circulation and the pulmonary circulation.
Systemic circulation:
- The systemic circulation pathway carries oxygen-rich blood from the heart to the body's tissues and organs.
- Oxygenated blood leaves the left side of the heart (left atrium) and is pumped out through the aorta to the rest of the body.
- The oxygen is then delivered to the tissues and organs, and deoxygenated blood returns to the heart through the superior vena cava and inferior vena cava.
Pulmonary circulation:
- The pulmonary circulation pathway carries deoxygenated blood from the heart to the lungs to pick up oxygen and release carbon dioxide.
- Deoxygenated blood leaves the right side of the heart (right ventricle) and is pumped to the lungs through the pulmonary artery.
- In the lungs, the blood picks up oxygen and releases carbon dioxide, then oxygenated blood returns to the heart through the pulmonary veins.
The figure-8 pattern is formed when the deoxygenated blood leaves the heart through the right side, travels to the lungs to pick up oxygen, returns to the heart through the pulmonary veins, and then is pumped out from the left side of the heart to the rest of the body. This continuous cycle of blood flow creates a figure-8 pattern in the circulatory system of mammals.