These data supply evidence that the test items accurately represent the processes of osmosis and diffusion.Student PerformanceThe most striking outcome would be the overall consistency of students’ response patterns across levels, semesters, and years (Figure two). Students commonly performed better on first-tier “What” things (odd numbers) than on second-tier reason “Why” things (even numbers) on each the ODCA and also the DODT (Figures 1 and 2 and Table 6), indicating that they normally can predict the outcome but have less understanding about the underlying mechanisms. With the nine ODCA question pairs, 3/4, 5/6, and 7/8 yielded the lowest combined content material eason values (Figure 1 and Table six), and hence reflected by far the most prevalent misconceptions amongst our students. Excerpts from these three item pairs are shown in Table 7, in addition to frequencies of student responses and variance amongst semesters in parentheses. Greater than 90 of all students appropriately indicated that particles (dissolved substances) would move from regions of high to low concentration (response 3a; Figure 1A and Table six). However, when asked to provide a explanation for their answer, quite a few faltered (Table six). The correct combined content eason ODCA responses, 3a and 4b, had been selected by 25 of nonbiology majors and lower-division biology students (Table 6).More than one-fourth (274 ) of students at every single course level chose response 4a, “crowded particles want to move to an location with extra room” (Table three, misconception 19; Table 7). That’s, a substantial proportion of our undergraduates attributed anthropomorphic qualities to substances in place of scientifically correct alternatives. Interviews corroborated these tendencies. When an interviewee was asked why she chosen 4a (“. . . crowded particles choose to move . . .”) in lieu of 4b (“the random motion of particles suspended inside a fluid results in their uniform distribution”), she stated that 4a seemed much more understandable and constant with her conceptualization from the diffusion procedure. “I just consider diffusion as. . .there is bunch of particles here and there aren’t any there, so it’s crowded. So [the particles] just move for the other side since. . .they choose to even out” (italicized word indicates emphasis by the speaker). When asked why she did not pick answer 4b, the student replied that while she knew that the particles moved randomly, she didn’t quite understand how such motion would lead to uniform distribution. Surveyed biology instructors similarly identified anthropomorphism as a problem for students. For instance, a college instructor with 10 years of knowledge noted that students feel molecules “want to diffuse.” A further instructor suggested that it is actually tricky for students to remove the concepts of “`vitalism’ and `volition’ on the element of your particles.”CBE–Life Sciences EducationOsmosis and Diffusion Conceptual AssessmentFigure 2C. Radar graph shows the percentage of upper-division biology majors (UD), by course and by semester, who chosen the appropriate response for every item on the ODCA. Things are grouped in to the three conceptual categories described inside the text. Note the similarity of functionality across semesters. S, spring semester; F, fall semester. Title Loaded From File Sample sizes appear in Table four.One-fourth of our students indicated that particles often hold moving till they’re uniformly distributed after which they stop moving (response 4c).