Are traditional laboratories in the core introductory biology courses teaching physiology majors the art and trade of science, or simply leaving them with a memory of trivial experiments done for unknown reasons? Our students, a population dominated by pre-med and physiology majors, think the latter and have encouraged us to challenge this model, and it turns out scientists and education researchers agree with our students (4, 31, 32). In an effort to remedy this, we began a long-term redesign of the introductory biology sequence to become what is now a sequence of inquiry laboratories we term "Teams and Streams" (TS). In these TS inquiry labs, student research teams pose a scientific question/hypothesis, propose an experimental design, perform multi-week investigations and then present their findings in various forms (web, interviews, and papers). The response to this classroom laboratory design has been overwhelmingly positive. In a qualitative study of student opinion (where 260 student responses were studied), surveys conducted at the end of semesters where traditional scripted labs were used (n = 70 comments) had predominantly negative opinions (80% negative responses), whereas the reverse was true for students (n = 190 comments) who participated in courses using the TS inquiry labs (78% positive responses). In a quantitative assessment of content knowledge, students who participated in new TS inquiry labs (n = 245) outscored their peers in traditional labs (n = 86) on Medical College Admission Test-style standardized exams (59.3 +/- 0.8% vs. 48.9 +/- 1.3%, respectively; P < 0.0001). We believe these quantitative data support the qualitative findings and suggest the TS inquiry lab approach increases student learning.

The relationship between multidrug resistance (MDR) P-glycoprotein expression and swelling-activated Cl- and K+ conductance was investigated in mouse NIH/3T3 fibroblasts and their colchicine-selected counterparts (COL1000, high P-glycoprotein). Whole cell patch-clamp and isotopic flux experiments confirmed that swelling-activated Cl- currents were induced by 20-30% bath dilution only in the MDR-expressing cell line. However, at bath dilutions > 30%, both cell lines developed Cl- currents that reached similar large magnitudes at higher dilution levels. Thus the apparent absolute difference in cell lines at lower dilutions is due to a shift in the response curve relating hypotonicity to Cl- conductance. At all dilutions and in both cell lines, the swelling-activated Cl- currents were outwardly rectifying, active at negative cell voltages, and inactivated at positive voltages. Verapamil (100 microM) and 1,9-dideoxyforskolin (100 microM), which inhibit P-glycoprotein drug transport, did not significantly inhibit the swelling-activated Cl- conductance efflux in the COL1000 cells also showed a leftward shift in the response curve to hypotonicity. These results indicate that response curve to hypotonicity. These results indicate that colchicine-selection for increased P-glycoprotein expression did not lead to the expression of swelling-activated Cl- channels, but instead enhanced a step in the pathway from bath dilution to regulatory volume decrease that is common to both K+ and Cl- channels.

In this study, we compared gains in student content learning over a 10-yr period in which the introductory biology laboratory curriculum was changed in two ways: an increase of inquiry and a reduction of content. Three laboratory formats were tested: traditional 1-wk-long cookbook laboratories, two 7-wk-long inquiry laboratories, and one 14-wk-long inquiry laboratory. As the level of inquiry increased, student learning gains on content exams trended upward even while traditional content coverage taught decreased. In a quantitative assessment of content knowledge, students who participated in the 14-wk-long inquiry laboratory format outscored their peers in both 7- and 1-wk-long lab formats on Medical College Admissions Test exam questions (scores of 64.73%, 61.97%, and 53.48%, respectively, P < 0.01). In a qualitative study of student opinions, surveys conducted at the end of semesters where traditional 1-wk laboratories (n = 167 students) were used had low response rates and predominately negative opinions (only 20% of responses were positive), whereas those who participated in 7-wk (n = 543) or 14-wk (n = 308) inquiry laboratories had high response rates and 71% and 96% positive reviews, respectively. In an assessment of traditional content coverage in courses, three indexes were averaged to calculate traditional forms of coverage and showed a decrease by 44% over the study period. We believe that the quantitative and qualitative data support greater student-driven inquiry in the classroom laboratory, which leads to deeper learning in fewer topic areas (less teaching) and can reap gains in scientific thinking and fundamental understanding applicable to a broader range of topic areas (more learning) in introductory biology.

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The authors studied gains in student learning when curriculum was changed to include an optional verbal final exam (VF). Students who passed the VF outscored peers on MCAT questions (66.4% [n=160] and 62% [n=285], respectively; p < 0.001), and passing the VF also correlated with higher performance in a range of upper-level science courses.