Introduction Close your eyes for a moment and place your hand over your chest. Feel that steady rhythm? Lub-dub, lub-dub, lub-dub. That’s your heart—your body’s hardest-working muscle, tirelessly pumping blood to keep you alive every second of every day. The heart is nothing short of a biological marvel. About the size of your fist, this […]

The Amazing Pump: How the Heart Keeps You Alive