Revisit the germinating seeds assessment probe to remind students the difference between germinated and non-germinated seeds.
Ask students the following questions:
(Note: When I first introduced this assessment probe, I actually assembled it. By this time, the seeds have germinated and have form parsley plants. As a class, we open the bell jar. Students are able to examine the seeds in the peat moss pellets. They should notice that some have germinated and some have not germinated. I have my students consider why some seeds have not germinated.)
This student lab is based on a lab from Vernier. (Note: I use the lab with some minor modifications that are described below.)
The following equipment is needed for this lab.
Using germinated and non-germinated peas that have been incubated at room temperature, in a cold water bath, and a warm water bath, the amount of oxygen gas and carbon dioxide gas released will be measured. Then the rate of respiration and rate of consumption will be determined by calculating a regression line.
See Determining the Rate of Cell Respiration student lab worksheet for more detailed instructions.
Students should share and compare their results. They should discuss the implication of their data by considering the differences seen between germinating and non-germinating seeds. They should also consider the effects temperature has on the respiration rate.
Possible student answers: The amount of oxygen in the biochamber is going down and the amount of carbon dioxide is going up.
Possible student answers: As peas germinate, the rate of cell respiration goes up.
Possible student answers: As temperature increases, the rate of cell respiration goes up.
Possible student answers: Germinating seeds needs oxygen and sugar to undergo cell respiration.
After the class discussion, students should summarize their findings in their lab notebook. Students will need to turn in their lab notebook for evaluation at the end of the period.