When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. The circulatory system consists of three independent systems that work together: the heart ...

The respiratory system allows air to reach the lungs, from which oxygen enters the blood and circulates to all body cells. This system also removes waste gases from the body and helps prevent disease ...

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Our bodies certainly are busy. All the different structures in us working together to achieve the ...