3.6 Applying the new explanatory model

  1. Applying the model. Students employ ideas from the yeast experiments and the digestion respiration combined model to explain why yeast inflate the balloon only to a certain circumference and then it does not really inflate anymore. The teacher helps students layer on ideas about limiting reactants and conditions for metabolic reactions.
  2. Revising the model. Students add new ideas (from yeast experiments) to the digestion respiration combined models in their journals.
Discussion Questions:1) How does Janet use this lesson to help students wrestle with unobservable ideas that the students had not fully considered to date? 2) What other phenomena might students be able to explain now?