| The purpose of this study was to develop a reliable and valid instrument designed to collect and provide information on college biology students' misconceptions about diffusion and osmosis concepts.; The Diffusion and Osmosis Diagnostic Test was developed by the procedures described by Treagust (1985). The final instrument consisted of 12 two-tier items. The test was administered to 123 Biology 2 (non-science majors) and 117 Biology 10 (science majors) students. Among the Biology 2 students, 41 were male and 82 were female. Among the Biology 10 students 51 were male and 66 were female.; The data analysis found that Biology 10 students had fewer misconceptions than Biology 2 students, and there was no significant difference in the number of misconceptions among male and female students.; A two-way analysis of covariance showed that math placement was a significant covariate, while number of science classes taken in high school was an insignificant covariate as measured by the Diffusion and Osmosis Diagnostic Test. The number of science courses taken in high school was dropped as a covariate. There was a significant difference for main effects among Biology 2 and Biology 10 students, no significant difference between male and female students, and no significant interaction between gender and Biology 2/Biology 10 students.; It was concluded that misconceptions about diffusion and osmosis exist in Biology 2 and Biology 10 students after studying these concepts. Biology 10 students had significantly fewer misconceptions than Biology 2 students in four general areas covered by 7 items on the Diffusion and Osmosis Diagnostic Test. The four general areas were: (1) The particulate nature and random motion of matter. (2) Concentration and tonicity. (3) The process of osmosis. (4) The influence of life forces on diffusion and osmosis. |
