The Department of Biology at Grinnell College has recently introduced a revised curriculum that emphasizes the process of science through investigative laboratories. Courses have been shifted from content-based teaching to inquiry-based teaching. These changes have highlighted some serious deficiencies in the area of plant biology, specifically students' lack of understanding or misconceptions about basic plant physiological processes such as photosynthesis, respiration and nitrogen fixation. We propose to address these deficiencies with an integrated approach that would introduce increasingly sophisticated treatments of these subjects starting with the first course in biology through a sophomore-level cell biology course and culminating in advanced work in upper level courses and independent research. To reinforce their work in these areas we want to provide students with ample 'hands-on' experience by allowing them to conduct physiological experiments of their own design using whole plants rather than plant extracts. This would require the purchase of eight physiological workstations and two growth chambers. Each workstation would include a PowerMac computer and three physiology packages containing equipment and software that will allow the measurement of 02 production with an 02 sensor, of CO2 utilization with an infra-red gas analyzer, and of nitrogen fixation with a H2 sensor. Students would be introduced to computer-based data acquisition and analysis, which are becoming standard methods for physiological studies. Students would also improve their quantitative skills by using computer software that will provide a variety of types of analyses of their data sets. The economy and versatility of these packages would make sophisticated methodologies available to a large number of students at every level of our curriculum, helping them integrate and master plant physiological principles, from the introductory student to the advanced research student.
