Creating a working model of the human blood circulatory system with LED lights can be an engaging way to visualize how blood flows through the body. The LED lights can represent oxygenated (bright red LED) and deoxygenated blood (blue LED), and a simple pump can simulate the heart pumping blood.
Materials Needed:
- LED lights (red and blue, to represent oxygenated and deoxygenated blood)
- Clear plastic tubes (to act as veins and arteries)
- DC water pump or air pump (to simulate the pumping action of the heart)
- Small water reservoir or container (for the “blood”)
- Wires and battery (for powering the LEDs)
- Cardboard or foam board (for making the human body outline)
- Red and blue colored water (optional, to represent blood in the tubes)
- Switch (optional, to control the LEDs and pump)
- Glue, tape, or adhesive (for assembling the model)
- Scissors or craft knife (for cutting and shaping)
Video Steps to Create the Model:
1. Create the Body Outline
- Draw or cut out a large human body shape on cardboard or foam board. This will serve as the base for your circulatory system model.
- Mark the positions of the heart, lungs, arteries, and veins where you’ll place the tubing and LEDs.
2. Prepare the LED Circuits
- Place red LEDs along the arteries (from the heart to the body) to represent oxygen-rich blood.
- Place blue LEDs along the veins (from the body back to the heart) to represent oxygen-poor blood.
- Ensure that each LED is wired properly. Connect the positive legs of the LEDs to the positive terminal of the battery and the negative legs to the negative terminal of the battery. You can connect the LEDs in parallel, so they light up simultaneously.
- You can use a switch to control the LEDs, making it easier to turn the system on and off.
3. Simulate the Heart with a Pump
- Install a DC water or air pump in the position of the heart.
- Connect clear tubing to the pump to represent arteries and veins.
- One tube will represent the artery taking blood from the heart to the body.
- Another tube will represent the vein bringing blood back to the heart.
- You can use colored water (red for arteries and blue for veins) to make the blood flow more realistic, or just have the pump circulate plain water.
4. Setting Up the Tubing
- Attach the clear plastic tubing along the arteries and veins in your diagram, guiding it through the lungs, arms, legs, etc., as shown in a real human circulatory system.
- The tube connected to the pump’s outlet will carry the “oxygenated blood” (red-colored water or red LEDs) from the heart to different parts of the body.
- The tube connected to the pump’s inlet will represent deoxygenated blood (blue-colored water or blue LEDs) coming back to the heart.
- Secure the tubing to the body outline using glue or tape.
5. Connect the Pump to Power
- Connect the DC pump to the battery and make sure it is able to circulate the water (if using water) or air (if using air) through the tubes.
- You may also want to install a switch to control the pump, allowing you to turn the pumping action on and off.
6. Assemble and Test the System
- Once the tubing, LEDs, and pump are in place, test the system:
- Turn on the LED lights to see the visual representation of oxygenated and deoxygenated blood.
- Activate the pump to simulate the blood flow. If using water, ensure that the pump moves the water smoothly through the tubes.
- Ensure that the red and blue LEDs light up properly and correspond to the right sections of the circulatory system (arteries for red, veins for blue).
7. Final Touches
- Label the parts of the system such as the heart, lungs, arteries, and veins.
- You can also decorate the model by drawing other body parts or using small cutouts to represent organs.
Key Concepts Demonstrated:
- Heart Function: The pump mimics the heart’s action of pumping blood.
- Arteries and Veins: The red LEDs/lighted tubes show oxygen-rich blood, while the blue LEDs/lighted tubes show oxygen-poor blood.
- Blood Flow: Water or air moving through the tubes represents how blood circulates from the heart to the body and back.
Optional Enhancements:
- Use a microcontroller (like an Arduino) to control the LEDs and pump in a more sophisticated way, simulating heartbeats.
- Add a second pump or valve to better mimic the flow of blood through the pulmonary circulation (from the heart to the lungs and back).
This model effectively illustrates how the human circulatory system works, showing the movement of blood through the body and the roles of the heart, arteries, and veins.