The aorta, a large blood vessel responsible for transporting oxygenated blood from the heart to the rest of the body, plays a ...

Circulatory system is the first organ system to become functional ... Heart has completely separated: 2 atria, 2 ventricles, 4 chambers, and adult bird has complete double circulation: low-pressure ...

Like all mammals, it has a circulation system that's made ... the heart twice on every loop - so we call it a double circulatory system. This needs to be very efficient because mammals require ...