Using tangible comparisons to power sources and the waste produced by them we are introduced to the digestive and excretory systems.
Digestion breaks down all the food we eat so the important nutrients and molecules can be absorbed into our circulatory system. All of our cells use the nutrients, and as a part of working, create waste that our body systems eliminate. Three very important systems remove waste from our cells. Learn about skin, the respiratory system and why the urinary system is our most important excretory system...
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