Today we held a class discussion focusing on the variables tested in the Baggie Garden experiments. To begin, students considered how their own manipulated variable affected seed germination. We then collected data from each group and used that information to identify temperature as one of the key factors in determining whether a seed will germinate. We also made the observation that seeds in the presence of water at room temperature did germinate, while seeds purchased from the store and kept dry at room temperature do not germinate. Therefore, water is another key factor for seed germination. Finally, we revisited the process of cellular respiration, identifying oxygen as the final requirement for seed germination.
Following the discussion, students had two options for the remainder of the class period. First, they could choose to read about cellular respiration in the textbook (pages 358-359, taking notes on the three stages of cellular respiration). Alternatively, students had the opportunity to build molecules using our new molecular modeling kits. Instructions for both activities can be found in the attached slide deck. Two students successfully modeled glucose, shown both in linear form (below left) and in ring form (below right).