{"id":52995,"date":"2025-09-23T17:04:29","date_gmt":"2025-09-23T08:04:29","guid":{"rendered":"https:\/\/phys-edu.net\/wp\/?p=52995"},"modified":"2026-09-27T05:16:50","modified_gmt":"2026-09-26T20:16:50","slug":"from-kerosene-pump-to-beating-heart-hands-on-science-class-to-feel-the-cardiac-mechanism","status":"publish","type":"post","link":"https:\/\/phys-edu.net\/wp\/?p=52995&lang=en","title":{"rendered":"Your Heart Pumps 8,000 Liters a Day! The Secret of “Valves” Revealed Through a Kerosene Pump"},"content":{"rendered":"

I’m Ken Kuwako, a Science Trainer. Every Day Is an Experiment!<\/strong><\/span><\/p>\n

\u201cThump, thump\u2026\u201d Our hearts have been working tirelessly from the moment we are born, never taking a break. You might be surprised to learn that this small organ, about the size of a clenched fist, pumps out roughly the equivalent of 40 large drums of blood every day<\/strong>. Textbooks tell us that \u201cthe heart has four chambers and valves that prevent blood from flowing backward,\u201d but simply reading that explanation can leave many middle school students thinking, \u201cI kind of get it\u2026 but not really.\u201d<\/p>\n

That\u2019s exactly when experiments can make all the difference. Believe it or not, you can experience the ingenious mechanism of this life-sustaining pump using just one familiar household item. In this article, I\u2019ll introduce a heart model experiment using a kerosene siphon pump, which I developed together with student teachers.<\/p>\n

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Kerosene siphon pumps are available at Seria and Daiso.<\/p>\n

Why Does Blood Flow in Only One Direction? Solve the Mystery with an Everyday Tool!<\/h3>\n

For an adult weighing around 50 kg, the amount of blood circulating through the body is said to be about 4 liters.<\/p>\n

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By contrast, each heartbeat pumps out about 60\u201380 milliliters of blood in an adult. Let\u2019s use 70 mL as an example. If the heart beats 80 times per minute (the typical range is said to be 60\u2013100 beats per minute), we can calculate the amount of blood pumped by the heart in one day as follows.<\/p>\n

70mL \u00d7 80 beats\/min \u00d7 60 min \u00d7 24 hours<\/p>\n

70 \u00d7 80 = 5,600 mL (per minute)
\n5,600 \u00d7 60 = 336,000 mL (per hour) = 336 L
\n336 \u00d7 24 = 8,064 L<\/p>\n

In other words, the heart pumps around 8,000 liters<\/b> of blood every day!<\/p>\n

There are only about 4 liters of blood in the body, yet the total amount pumped in a day is about 2,000 times that much. The reason for this huge difference is the fact that the blood continuously circulates around the body again and again<\/strong>. The heart isn\u2019t constantly making new blood. Instead, it keeps circulating the same limited supply of blood over and over at an astonishing rate.<\/p>\n

When we think of a kerosene siphon pump as a model of the heart<\/b>, we can clearly see the role of the tiny \u201cvalve\u201d inside the pump. And that little valve turns out to be the key to understanding how the heart works.<\/p>\n

Experiment Setup: Build a Life-Saving Pump with a 100-Yen-Shop Item<\/h3>\n

The materials are incredibly simple. You can easily find everything you need at home or at a 100-yen shop.<\/p>\n

\u3010What You\u2019ll Need\u3011<\/b><\/p>\n

    \n
  • Two kerosene siphon pumps<\/b>:<\/li>\n
  • One with the valve removed<\/b><\/li>\n
  • One with the valve left in place<\/b><\/li>\n
  • Water and red food coloring (to create \u201cblood\u201d)<\/li>\n<\/ul>\n

    \"\"<\/p>\n

      \n
    • A transparent beaker or container (so you can easily observe the flow of the \u201cblood\u201d)<\/li>\n
    • A tray or towel (to keep your table from getting wet)<\/li>\n<\/ul>\n

      \u3010Experiment Procedure\u3011<\/b><\/p>\n

      Prepare some \u201cblood\u201d by adding red food coloring to water. First, let\u2019s see what happens when you operate the pump with the valve removed<\/b>.<\/p>\n

      \u2192 Whether you push or pull the pump, water flows in and out through both hoses. The result? The \u201cblood\u201d can\u2019t travel around the body in a single direction. Next, try the same thing with the regular pump with its valve in place<\/b>.<\/p>\n

      \u2192 This time, something amazing happens: the water is pumped forcefully in one direction. There is no backflow at all. This is exactly what makes the flow of life possible, carrying oxygen and nutrients throughout the body!<\/p>\n