Objective
By the end of this lesson, you will be able to understand the respiratory system by comparing it to a tree.
Materials and Prep
- Pen or pencil
- Blank paper
No prior knowledge is required for this lesson.
Activities
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Draw a large tree on your paper. Label the trunk as "trachea" and the branches as "bronchi".
Explain that just like the trunk and branches of a tree transport water and nutrients, the trachea and bronchi transport air.
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Draw small leaves at the ends of the branches and label them as "alveoli".
Compare the leaves to the alveoli, explaining that just like leaves exchange gases with the air, alveoli exchange oxygen and carbon dioxide with the blood.
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Take a deep breath and feel your chest rise. Explain that when we breathe in, our diaphragm muscle moves down, just like when we inhale, the chest cavity expands.
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Exhale slowly and feel your chest fall. Explain that when we breathe out, our diaphragm moves up, just like when we exhale, the chest cavity gets smaller.
Third Grade Talking Points
- "The respiratory system helps us breathe and get oxygen into our bodies."
- "The trachea is like the trunk of a tree, and the bronchi are like the branches."
- "The alveoli are like the leaves of a tree, and they help exchange oxygen and carbon dioxide."
- "When we inhale, our chest expands because our diaphragm moves down."
- "When we exhale, our chest gets smaller because our diaphragm moves up."