human respiratory system (lungs ) working model for school science exhibition - diy - diypandit

human respiratory system (lungs ) working model for school science exhibition project - diy - diypandit #respiratorysystem #lungs #workingmodel #workingproject #scienceexhibition #diy #diypandit **Introduction** Good morning, respected judges, teachers, and my dear friends. Today, I am going to explain my science project, the **Human Respiratory System Working Model**. The respiratory system is one of the most important systems in our body. It helps us breathe by taking in oxygen and removing carbon dioxide. **Main Parts of the Respiratory System** The main parts of the respiratory system are the nose, trachea, bronchi, lungs, and diaphragm. The nose filters the air we breathe. The trachea, also called the windpipe, carries air towards the lungs. The trachea divides into two bronchi, which carry air into the left and right lungs. The lungs contain tiny air sacs called alveoli, where oxygen and carbon dioxide are exchanged between the air and the blood. **Working Principle of the Model** This model demonstrates the basic mechanism of breathing using balloons and a tube. The balloons represent the lungs, and the tube represents the airway. The transparent tube helps demonstrate the movement of air into and out of the lungs. **How Does It Work?** When we breathe in, the diaphragm contracts and moves downward. This increases the volume of the chest cavity and decreases the air pressure inside the lungs. As a result, air enters the lungs, and they expand. When we breathe out, the diaphragm relaxes and moves upward. The volume of the chest cavity decreases, increasing the pressure inside the lungs. Air moves out, and the lungs become smaller. In our model, air passes through the tube and causes the balloons to inflate or deflate, demonstrating the basic process of breathing. **Importance of the Respiratory System** The respiratory system supplies oxygen to our body. Our cells use oxygen to release energy from food. It also helps remove carbon dioxide, which is a waste product of cellular respiration. **Conclusion** To conclude, this working model helps us understand how air enters and leaves the lungs during breathing. It demonstrates how important the respiratory system is for our survival and how a simple working model can explain a complex biological process. Thank you! Five viva questions with answers 1. What is the main function of the respiratory system? Answer: It supplies oxygen to the body and removes carbon dioxide. 2. What do the balloons represent in this model? Answer: The balloons represent the lungs. 3. What is the function of the trachea? Answer: The trachea, or windpipe, carries air from the upper airway towards the bronchi and lungs. 4. What happens to the diaphragm when we breathe in? Answer: The diaphragm contracts and moves downward, increasing the volume of the chest cavity and allowing air to enter the lungs. 5. Where does the exchange of oxygen and carbon dioxide take place? Answer: Gas exchange takes place in the alveoli, the tiny air sacs inside the lungs.