Analysis of Assessments for Biochemistry Students of Varying Chemistry Backgrounds in Thermodynamics and Kinetics of Chemical Reactions as well as Research Skills

Abstract

Threshold concepts represent abstract topics in a subject that students must grasp in order to advance understanding in the subject. In Biochemistry, they include several topics related to thermodynamics and kinetics of chemical reactions including, free energy, thermodynamics, and steady state. Many of these topics are covered in the introductory chemistry sequence, which is taught traditionally as a year of general chemistry followed by organic. Chemistry courses at Stockton University are presented in a different order: general I, organic I and II and general II. In the Biochemistry classes at Stockton, students have varied chemistry backgrounds. A Previous assessment was designed to test student’s knowledge in several threshold concepts as a pre and post‐test and correlate it with amount of chemistry classes previously taken. Students scored the lowest marks in questions related to free energy and thermodynamics: the initial scores were lowest and the lowest amount of improvement was observed as well. This was true regardless of number of previous chemistry courses taken. The goal of this project was to investigate the reason for the low scores. A new assessment was used and tested on 170 Biochemistry students as a pre ‐test at the beginning of the semester and a post‐test at the end. In order to separate knowledge of the concept from knowledge of definitions and symbols, questions were designed to assess both. Half of the questions required students to correctly identify symbols and definitions for the terms related to steady state, thermodynamics and kinetics. The other required students to predict the outcomes if a change occurs without requiring the use of symbols to represent the key terms. Results are presented based on both areas. In addition to questions on these topics, students are also assessed for some of the outcomes listed in the skills in the ASBMB Foundational Concepts. The skills assessed required the students to interpret the results of an enzyme assay in which various mistakes were made as well as comment on experimental design and best way to express results. In addition to these higher level questions, there were also ones on how to prepare solutions. The scores are also related to the amount of Chemistry and Biology classes previously taken.