Arteries and veins contain blood with different oxygen content, etc.
Arteries are responsible for transporting oxygen-rich blood to the surrounding tissues, from the heart to the surrounding organs, where under normal conditions the blood flows with a partial pressure of oxygen of 100 mmHg and an oxygen saturation of 95-98%;
Veins are responsible for recycling blood from various organs into the heart, where the partial pressure of oxygen in the flowing blood is about 40mmHg and the oxygen saturation is 70%-75%.
In addition, arterial blood vessels have thicker walls, greater elasticity and higher pressure, and bleeding after arterial rupture and hemorrhage is large and difficult to control, while venous blood vessels have thinner walls, larger vascular diameters, and less elasticity, and bleeding after venous rupture is small and easy to control.