Hi there! Have you ever noticed all the heart shapes around on Valentine’s Day? They look like this ❤️, but did you know the real heart inside our bodies looks very different? Let’s explore this amazing organ together!
Your heart is super important because it pumps blood all around your body. It’s like a little engine that keeps you going! When you visit the doctor, they often listen to your heartbeat to make sure you’re healthy. Have you ever wondered why it’s called a “heartbeat”? It’s because it makes a sound like this: thump thump, thump thump. But why does it make that sound?
For a long time, people knew the heart made a sound, but they didn’t know exactly why. It’s hard to see inside our bodies, but there’s a special animal that can help us understand. Meet the glass frog! Its skin is see-through, so you can actually see its heart beating. Isn’t that cool?
Thanks to technology, we can now see our own hearts beating. When your heart beats, it squeezes, kind of like when you squeeze your fist. Scientists discovered that the heart is a muscle, just like the muscles in your arms. But instead of lifting things, this muscle squeezes blood through your body.
Imagine a rubber duck. When you squeeze it, water squirts out, and when you let go, it fills back up with water. Your heart works in a similar way! It has hollow parts that fill with blood. When your heart squeezes, it pushes blood out through tubes called blood vessels. These vessels carry blood all over your body.
Have you ever felt your pulse? It’s the little push you feel when blood moves through your blood vessels. You can feel it on your wrist. Each time your heart beats, it gives a push, and that’s your pulse. Doctors feel your pulse to see how fast your heart is beating.
So, the heart is a muscle that pumps blood by squeezing it into blood vessels. This helps blood reach every part of your body. Isn’t that amazing?
Thanks for joining this heart adventure! Stay curious, and keep exploring the wonders around you!
Heart Beat Experiment: Let’s try to feel our own heartbeat! Find a quiet place and sit down comfortably. Place two fingers on your wrist or the side of your neck. Can you feel the little thump? Count how many times you feel it in one minute. Try this after running in place for a minute and see if it changes. Why do you think it changes?
Make a Heart Model: Create a simple model of the heart using a small plastic bottle, some water, and a balloon. Fill the bottle halfway with water, stretch the balloon over the top, and poke a small hole in the balloon. Squeeze the bottle gently and watch how the water squirts out, just like how your heart pumps blood. What happens when you squeeze harder or softer?
Heart Shape Hunt: Go on a heart shape hunt around your home or school. Look for objects that are shaped like a heart. Draw or take pictures of the heart shapes you find. Discuss with a friend or family member how these shapes are different from the real heart inside your body. Why do you think we use this shape to represent love and the heart?
Sure! Here’s a sanitized version of the transcript:
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Hi, it’s Doug. Every Valentine’s Day, you see a bunch of hearts that look like this. But it’s interesting—I have here a wooden model of a human heart. This is the actual shape of the heart inside our bodies. They don’t look anything alike! Someone named Kayla has a question about hearts. Let’s give her a call now.
– Hi Doug!
– Hi Kayla!
– I have a question for you. How does your heart pump blood?
– That’s a great question! This is a picture of what a real human heart looks like. You probably know that the job of the heart is to pump blood through your body. It’s one of the most important organs; you couldn’t live without it. It’s so important that when you go for a checkup, what’s the first thing the doctor does? They listen for the sound of your heartbeat to make sure that you’re healthy.
Did you ever think about why we call it a heartbeat? It’s kind of like the rhythm in a song; it just keeps repeating, making the same sound over and over again—thump thump, thump thump. Why does it make a sound like that? Sure, you know it’s pumping blood. But what exactly is going on that causes it to make that thump thump sound?
Now would be a good time to pause the video and discuss. Okay, you ready? Well, people have always known that the heart makes a sound, but it wasn’t obvious what exactly the heart is doing when it makes that sound. That’s because, while it’s easy to hear the heart, it’s not easy to see it.
But what if I told you that there’s an animal that does? Check this out. This is called a glass frog. Its skin isn’t made of glass; that’s just its name. But the skin really is see-through, especially on the underside. Look right there. You see that? That’s the frog’s heart beating. So this is what a heart looks like each time it beats.
Thanks to modern technology, we now have imaging that lets us see our own hearts as they beat. This is an animation showing what your heart looks like inside your body. Do you notice now what the heartbeat is? With each beat, you can see the heart giving a big squeeze, almost like if you squeeze your fist.
When scientists first discovered this, it reminded them of other parts of the body that are good at squeezing, like your hands and arms. The parts of the body that are good at squeezing are muscles. By looking at the actual heart, scientists figured out that, in fact, the heart is a muscle. But unlike the muscles you have in your arm, instead of squeezing to pick things up or hold things, the heart is a muscle that squeezes blood around your body.
It’s actually a lot like a squeeze toy. Think about it. When you squeeze a rubber duck, it squirts out water. And then if you dunk it back into the water again and release it, it sucks water back in, right? Filling up again. Your heart is very similar to this. Just like a rubber duck is hollow and can be filled with water, your heart contains hollow parts on the inside that can be filled up with blood.
When your heart beats and squeezes, it pushes out blood. Now, as you might guess, when the heart squeezes, it doesn’t just send blood squirting all over the place. Blood leaves the heart in tubes called blood vessels. There are also blood vessels that bring blood into the heart to refill it. When the heart stops squeezing, it pulls blood in from those tubes, just like the rubber duck fills back up with water when you stop squeezing it.
Those blood vessels then go to all the different parts of the body that need blood. You’ve probably noticed before that you can even see some of the blood vessels in your own body, like if you look at the inside of your wrist or elbow. Each time the heart pushes blood through the blood vessels, that gives a little push on the vessel. That’s called a pulse.
You can actually feel blood moving through the vessels if you put your fingers on your wrist. There are blood vessels inside your wrist. So when you feel your pulse there, what you’re really feeling is the push from your heart squeezing the blood into the blood vessels. That’s what a doctor is feeling when they’re checking your pulse.
If a doctor wants to find out how fast your heart is beating, she doesn’t have to look at your heart. Instead, she can just feel for your pulse. Each push of the blood is actually the beat of your heart.
So in summary, the heart is a muscle that pumps blood to all parts of your body by squeezing blood into tubes called blood vessels. As the blood goes through all the vessels in your body, it pushes on them—that’s your pulse.
That’s all for this week’s question. Thanks, Kayla, for asking it! Now, we have something special for this week’s episode. My friends and I here at Mystery Science have created a step-by-step activity that combines science with art. You can find a link to the activity at the end of this video.
For the next episode, we’re choosing questions about the Olympics. I found three questions submitted to me that I’m thinking about answering. When this video is done playing, you’ll get to vote on one. You can choose from, “Why do we have the Olympics?” “What are some of the weirdest sports in the Olympics?” or “How do they choose which sports get to be in the Olympics?”
So submit your vote when the video is over. I want to hear from all of you watching. There are mysteries all around us. Stay curious, and see you next week!
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Let me know if you need any further modifications!
