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Here is the heart. It was actually done in layers over several days. Each day, I would build on top of the existing work. Here's the breakdown:
Day 1: I taught about arteries, veins and capilaries as well as the travel to and from the heart. At this point, the heart was nothing but a blob of reddish hue.
Day 2: We began the discussion of how blood enters the heart (Inferior and Superior Vena Cava), exits to the lungs (pulmonary arteries, re-enters the heart from the lungs (pulmonary veins) and finally gets pumped back out to the body (Aorta).
Day 3: The atriums and ventricles and valves along with a recap.
Here's another chalking I did. Can you guess what I was going for?
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If you said, "zits," I guess I should go back to the drawing board (literally), or you should go back to 5th grade. If you said, "aveoli," you are correct and I did my job well because I made this stuff.