Middle School

Cellular respiration, food, energy

Why is bread usually soft and airy?  Experiment to see how yeast uses cellular respiration and is affected by sugar!


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Learning Objectives

Students will know

  • Cellular respiration
  • Chemical reactions

Students will understand

  • Sugar is needed for cellular respiration to occur.
  • The sugar is rearranged with oxygen to produce energy in addition to water and carbon dioxide.

Students will be able to

  • Conduct an experiment to determine the effect of sugar on yeast’s ability to respire
  • Use a model to show to explain that molecules are broken apart and rearranged to form energy
Standards Alignment + Connections

Next Generation Science Standards Connections

MS-LS1-7: Develop a model to describe how food is rearranged through chemical reactions forming new molecules that support growth and/or release energy as this matter moves through an organism.

How to Run the Experiment

Materials You Will Need

  • Two empty water bottles
  • Two balloons
  • Warm water
  • Sugar
  • Measuring spoons
  • Funnel
  • Yeast
  • Marker

Additional Resources