The circulatory system

The pump

A body and its heart Four chambers The beat The valves The heart's own arteries The heart's veins

The short loop

Through the lungs Air and blood

The long loop

The aorta Head and arms The brain's arteries The arm Blood pressure The gut The kidneys The thigh Below the knee Every artery Capillaries

The way back

The venae cavae Veins under the skin The muscle pump The portal system The whole circuit

Before birth

Before the first breath The first breath

The blood itself

Where blood is made Where blood ends

How the circuit was found

2nd centuryGalen about 1242Ibn al-Nafis 1628The bandaged arm 1628Harvey's sum 1661Malpighi's capillaries

The circulatory system

The heart, the arteries, the veins and how the blood moves through them. It follows the blood from the heart to the lungs, around the body and back, and also covers the circulation before birth and how Harvey proved in 1628 that the blood circulates.