Your heart is a pump, and it’s a lot like the pumps that people manufacture.
A pump needs a source of energy to function. If you work a pump with your hands, that’s an example of mechanical energy. Or you can trigger it with electricity, which is how your heart works.
The tiny electric sparks your heart makes cause cardiac, or heart, muscles to contract. The contractions, or heartbeats, are steady and regular, thanks to a built-in timer. So what happens if your heart’s timer stops ticking? You can get a pacemaker. That’s a small box that creates timed sparks for your heart.
Although your heart is triggered by electricity, it also has moving parts. Valves open and shut, muscles squeeze and push, and the blood flows through expandable tubes.
The heart pump has one job: to control the flow of liquid. It pumps the liquid uphill against gravity and keeps blood flowing to all parts of the body.
