The Human Heart
A pump beating 70 times a minute, 3 billion times in a lifetime
Summary
The heart is a muscular pump with four chambers (the right and left atria and ventricles). With each beat it sends oxygen-poor blood to the lungs and oxygen-rich blood to the body. An adult human heart beats about 100,000 times a day.
In depth
This organ, about the size of your fist, is one of the hardest-working muscles in your body: it works for a lifetime without stopping or tiring. The heart is divided into four chambers: two atria at the top and two ventricles at the bottom. The right side pumps oxygen-poor blood returning from the body to the lungs; the left side sends oxygen-rich blood from the lungs to the whole body. This double loop carries oxygen to every cell through a network of blood vessels about 100,000 km long. Every beat is triggered by the heart's own specialised pacemaker cells (the sinoatrial node), which is why a heart can keep beating for a while even outside the body. The electrical signal that drives the beat is measured with an ECG, which shows the characteristic P-QRS-T waves.
Rate The Human Heart
What did you think of this content? Click the stars to leave your rating.
Leave a Comment and Rating