Undergraduate Student Explanations About Molecular Processes in Information Flow and Transfer in Biology


National calls to improve science education include focusing on scientific practices coupled with learning disciplinary
core ideas. Among the practices is constructing explanations, which include a mechanism in cellular and molecular
biology, and are used by experts to make predictions about phenomena. In this work, we developed an assessment of
undergraduate mechanistic explanations about the biology core concept of genetic information flow. We collected and
coded 346 undergraduate student written responses. Using a mechanistic framework, we developed a rubric to capture
student knowledge in their written responses. The rubric captures whether students provide a fully mechanistic, submolecular
explanation of transcription, which is a key process in genetic information flow. We used this rubric to
compare five item versions and found that one version elicited fully mechanistic explanations from 20% of students,
compared to between 2 and 13% from other versions. This version included the element of time, by indicating that a
new RNA was formed as part of transcription. We also found that students integrated a median of two related ideas
with their explanation of transcription. Our work demonstrates that careful wording is essential for item writing and that
students can explain molecular processes like transcription by leveraging sub-molecular mechanisms.


Juli Uhl, Kevin Haudek

Year of Publication


Conference Name

NARST Annual Conference

Date Published



National Association for Research on Science Teaching and Learning

Conference Location