Learning in An Inquiry-Driven Plant Physiology Laboratory

Plant physiology is best explored through participatory ac- tivities, where students are closely engaged in the process of dis- covery. A two-stage approach to instruction was implemented to enrich the learning in an undergraduate plant physiology labo- ratory. First, a core of 10 experiments was developed to provide structured, hands-on experience and to teach the principles and skills of modern physiological analyses. During Week 11 of a 15- wk semester, students observe a demonstration of a plant re- sponse, where the underlying cause of the phenomenon is not ev- ident. Working together in small groups, students hypothesize on the mechanisms that may be involved. They choose among al- ternative lines of inquiry and decide which variables will be most informative in revealing the underlying nature of the prob- lem. Each research team presents a study plan, and hypotheses and experimental approaches are defended. Results of team ex- periments are presented during Week 15. To date, inquiry-based projects have focused on the roles of (i) ethylene in seedling de- velopment in mouse-ear cress (Arabidopsis thaliana L. (Heynh.)) and tomato (Lycopersicon esculentum Mill.), (ii) glycinebetaine in drought tolerance of maize (Zea mays L.), (iii) catalase in chilling sensitivity of tomato, and (iv) ascorbic acid in oxidative stress in tomato. The Chilling-Injury Problem utilized in 1996 and 1997 is described, and pedagogical advantages as well as chal- lenges to implementation are discussed. The approach appears to foster a capacity for connective, integrative thinking. Stu- dents develop competency in judging the reliability and signifi- cance of experimental results, and in evaluating whether their conclusions are justified by the data.