Diagnosing secondary students' misconceptions of photosynthesis and respiration in plants using a two-tier multiple choice instrument

Abstract

A two-tier multiple-choice instrument is described which reliably and validly diagnoses secondary students' understanding of photosynthesis and respiration in plants. The first tier of each item relates to content based on propositional knowledge statements. The second tier consists of reasons based on students' responses to interviews, open-ended questions, and/or previous research. These reasons include identified misconceptions and a scientifically acceptable answer. The results of the study highlight the consistency of students' misconceptions across secondary year levels and indicate that a high percentage of secondary students do not comprehend the nature and function of respiration and have little understanding of the relationship between photosynthesis and respiration in plants. Recommendations are made for use of the instrument by classroom biology teachers.