 Drastic. Hey everybody, Dr. O. In this video I want to talk about the most amazing, sophisticated living pump in the world, and that is your heart. So I'm sure you've heard the heart called a pump and called a muscle. We're going to talk about what makes this heart so amazing at its job, which is to pump blood. So if your heart beats, you'll look at the heart here, but look if it beats about 75 beats a minute, that's going to be 108,000 heart beats a day, 39 million a year, and then give or take about 3.2 billion heart beats in your lifetime depending on how long you live. If each one of these pumps squeezes out about 70 milliliters of blood, which is the most, the average stroke volume, that's about 5.25 liters per minute. That would be 14,000 liters per day, which means in a year your heart is going to pump 2.6 million gallons of blood through your 60 to 100,000 miles of blood vessels depending on the size. So those are just some amazing stats about your heart, but how does it do it and how is it so effective? The first thing I think of is how does it do this without taking a break? I couldn't do 3.2 billion bicep curls in a row without needing a break, so we'll talk about that. All right, so here we see the heart musculature. What makes the heart so amazing is how the muscles swirl around to form your heart in a figure eight pattern. So you basically have a figure eight pattern of musculature in the top of the heart, the atria, and another figure eight pattern at the bottom. And the reason that's important is because the heart basically rings itself out like a sponge and then relaxes. So when it beats, it rings itself out like a sponge, which is much more efficient way of pumping the blood out of the heart. And then when it relaxes and kind of uncoils, that sucks blood into it. So most of the blood that's actually sucked into the heart is just happening from this springing and unspringing, if you want to call it that. So the shape of the heart musculature is one of the things that's really amazing about it. The other thing is heart muscle cells. So we would have covered heart muscle cells way back when we talked about tissues. What makes heart muscle cells special is these intercalated discs, which you can see here, which means that it's basically all of your heart muscle cells are connected, which means that one stimulus can cause all of these cells to contract as a unit instead of having individual motor units like you'd see with your musculoskeletal system. Another thing that makes heart muscle tissue amazing is these cells, they have really long refractory periods. Now it keeps the heart from basically twitching and then not doing its job as a pump. But the reason that's so important is because since your heart never gets to take a break, what it does is it takes a break at the end of contraction. So mid contraction, these heart muscle cells get to take this kind of rest period, which allows them to keep going and going and going without your heart seizing up and stopping to work. So all right, those are just some interesting facts about the heart, what makes it such an amazing sophisticated muscular pump. And now let's dive into all the details. I hope this helps. Have a wonderful day. Be blessed.