HS-LS2-5 Respiration Lab

One of the really important HS-LS2-5 performance expectations is that students know the inputs and outputs of cellular respiration.  The video below shows a lab I've used for years with my biology students to teach this concept.


The word equation for cellular respiration is summarized below.

glucose (sugar)  +  oxygen  ->  carbon dioxide  +  water  

Students perform the experiment using yeast and apple juice.  I have also used sugar water or solutions of different sugars.  The three trials the students typically do include...

1. warm water
2. room temperature water
3. cold water

The lab also provides an opportunity to review or introduce factors can affect the speed of a chemical reaction (HS-PS1-5)

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