Where Is Your Heart?
Your heart is a hollow organ in the center of your chest. Although you may feel your heart beat when you place your hand over it, your heart is not right under your skin. Instead, your heart is behind your breastbone, inside your ribcage, and between your lungs (Figure 1).
Your heart is part of the circulatory system, which also includes your blood vessels and lungs.
What Does Your Heart Look Like?
An average adult heart is about the shape and size of a closed fist. Like a valentine heart, yours is slightly pointed at the lower end. The pointed end is called the apex (Figure 2).
What Does Your Heart Do?
Although your heart is hollow, it isn't empty. In an average adult, about 5 quarts (4.7 liters) of blood flow through the heart each minute. The main job of your heart is to pump that blood, which is full of oxygen and nutrients, through your entire body. Your organs (like your brain, kidneys, and liver) will stop working if they don't get oxygen and nutrients from blood.
Why Is Your Heart Called a Muscle?
Your heart's walls are made mostly of strong muscle, called the myocardium. The myocardium is the strongest, hardest-working muscle in your body. It continuously pumps your blood through 60,000 miles (96,560 kilometers) of blood vessels for a lifetime, without rest!
Next: Heart Chambers
Q. What is the muscle in your heart also the strongest muscle in your body called?