skip to main content
US FlagAn official website of the United States government
dot gov icon
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
https lock icon
Secure .gov websites use HTTPS
A lock ( lock ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.


Title: Punnett Squares or Protein Production? The Expert–Novice Divide for Conceptions of Genes and Gene Expression
Concepts of molecular biology and genetics are difficult for many biology undergraduate students to master yet are crucial for deep understanding of how life works. By asking students to draw their ideas, we attempted to uncover the mental models about genes and gene expression held by biology students ( n = 23) and experts ( n = 18) using semistructured interviews. A large divide was identified between novice and expert conceptions. While experts typically drew box-and-line representations and thought about genes as regions of DNA that were used to encode products, students typically drew whole chromosomes rather than focusing on gene structure and conflated gene expression with simple phenotypic outcomes. Experts universally described gene expression as a set of molecular processes involving transcription and translation, whereas students often associated gene expression with Punnett squares and phenotypic outcomes. Follow-up survey data containing a ranking question confirmed students’ alignment of their mental models with the images uncovered during interviews ( n = 156 undergraduate biology students) and indicated that Advanced students demonstrate a shift toward expert-like thinking. An analysis of 14 commonly used biology textbooks did not show any relationship between Punnett squares and discussions of gene expression, so it is doubtful students’ ideas originate directly from textbook reading assignments. Our findings add to the literature about mechanistic reasoning abilities of learners and provide new insights into how biology students think about genes and gene expression.  more » « less
Award ID(s):
1757477
PAR ID:
10353791
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Offerdahl, Erika
Date Published:
Journal Name:
CBE—Life Sciences Education
Volume:
20
Issue:
4
ISSN:
1931-7913
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. Undergraduate biology educators strive to understand how to best teach students the concepts of climate change. The root of this understanding is the establishment of what students know about climate change. This research aims to describe undergraduate biology students’ conceptions of climate change and their argument practices and associated cognitive biases in how they think about the topic. We used qualitative conception interviews to obtain data from 26 American biology undergraduate students who predicted how climate change would affect a forested ecosystem after an average of 1° increase in Fahrenheit (0.5°C change) over 25 years. Through deductive coding, we found the majority of students’ predictions agreed with expert ideas. However, the students used various argument strategies (i.e., Reasoning and Cognitive Biases) in defending their choices, including Ecological Explanations, Observations, Anchoring, and Contrast Effects. 
    more » « less
  2. Research Problem: Climate change is one of the most important environmental, social, and economic issues of our time. The documented impacts of climate change are extensive. Climate change education can help students link this global issue to students’ everyday lives, foster a climate-literate public, and serve as motivation for action. Yet prior to instructional interventions, the first step in promoting conceptual change is to describe expert and novice conceptions or mental models of the topic (Treagust and Duit 2009). Published studies about students’ climate change knowledge primarily stem from the earth and atmospheric sciences, and focus on students’ knowledge of the mechanisms causing global warming and of the abiotic systems important to climate change. Limited research has documented undergraduate students’ knowledge about the biotic impacts of climate change. Our goal was to describe student/novice and instructor/expert conceptual knowledge of the biotic impacts of climate change. Research Design: We conducted interviews with 30 undergraduates and 10 instructors who are students or teaching in Introductory Biology or Ecology classes. Our semi-structured interview protocol probed participants’ conceptions of the mechanisms, outcomes and levels of impact that climate change has on the biological world. Participants were taken from varying institutions across the US (Baccalaureate, Master’s, and Doctoral). Analyses: Following transcription of all interviews, we used thematic coding analysis to describe novice and expert conceptions of the biotic impacts to climate change. We also compared across interview populations to describe how novice and expert conceptions compare. Contribution: Our findings contribute understanding of biology student and expert knowledge of the biotic impacts of climate change and contribute more broadly to the field of climate science where research on understanding of the biotic impacts of climate change is minimal. Our work will represent a novel perspective because most climate education research at the university-level has focused on earth and atmospheric science students. Further, this work is the first step in a larger project that aims to develop valid and reliable concept inventory related to biotic impacts of climate change – an instrument sorely needed to properly address improvements to climate change education. 
    more » « less
  3. Fankhauser, Sarah (Ed.)
    ABSTRACT Visual representations in molecular biology tend to follow a set of shared conventions for using certain shapes and symbols to convey information about the size and structure of nucleotides, genes, and chromosomes. Understanding how and why biologists use these conventions to represent DNA is a key part of visual literacy in molecular biology. Visual literacy, which is the ability to read and interpret visual representations, encompasses a set of skills that are necessary for biologists to effectively use models to communicate about molecular structures that cannot be directly observed. To gauge students’ visual literacy skills, we conducted semi-structured interviews with undergraduate students who had completed at least a year of biology courses. We asked students to draw and interpret figures of nucleotides, genes, and chromosomes, and we analyzed their drawings for adherence to conventions for representing scale and abstraction. We found that 77% of students made errors in representing scale, and 86% of students made errors in representing abstraction. We also observed that about half of the students in our sample used the conventional shapes and symbols to represent DNA in unconventional ways. These unconventional sketches may signal an incomplete understanding of the structure and function of DNA. Our findings indicate that students may need additional instructional support to interpret the conventions in common representations of DNA. We highlight opportunities for instructors to scaffold visual literacy skills into their teaching to help students better understand visual conventions for representing scale and abstraction in molecular biology. 
    more » « less
  4. The active learning student-centered teaching approach process-oriented guided inquiry learning (POGIL) is a stimulating peer-based pedagogical method gaining momentum based on reported students’ outcomes that align with STEM undergraduate goals and objectives and job market competencies. Specific advanced topics in biology are intractable to many undergraduate students and require innovative, collaborative methods to produce desired learning outcomes. Chemistry instructors originally designed POGIL, and while biology-based POGILs are present in the literature, there is a limited amount of POGILs available in molecular biology. Thus, the current article illustrates a POGIL exercise that explores the central dogma, a fundamental principle in molecular biology. The central dogma of molecular biology provides a framework for gene expression processes and describes the flow of genetic information in living organisms. The central dogma describes how DNA nucleotides are transcribed into RNA nucleotides and translated into proteins. This seminal concept of molecular biology is critical to student understanding in introductory and advanced biological sciences courses. The POGIL exercise is organized based on the learning cycle model associated with inquiry-focused teaching techniques. The learning cycle model promotes gradual concept comprehension and real-world utilization. An increase in molecular biology POGIL exercises is required to improve student understanding and course grades in molecular biology or related disciplines. Examining the efficacy of using the current molecular biology POGIL exercise is necessary from the perspectives of undergraduate students and biology faculty to fortify POGIL usage at colleges and universities. 
    more » « less
  5. null (Ed.)
    Inferring phenotypic outcomes from genomic features is both a promise and challenge for systems biology. Using gene expression data to predict phenotypic outcomes, and functionally validating the genes with predictive powers are two challenges we address in this study. We applied an evolutionarily informed machine learning approach to predict phenotypes based on transcriptome responses shared both within and across species. Specifically, we exploited the phenotypic diversity in nitrogen use efficiency and evolutionarily conserved transcriptome responses to nitrogen treatments across Arabidopsis accessions and maize varieties. We demonstrate that using evolutionarily conserved nitrogen responsive genes is a biologically principled approach to reduce the feature dimensionality in machine learning that ultimately improved the predictive power of our gene-to-trait models. Further, we functionally validated seven candidate transcription factors with predictive power for NUE outcomes in Arabidopsis and one in maize. Moreover, application of our evolutionarily informed pipeline to other species including rice and mice models underscores its potential to uncover genes affecting any physiological or clinical traits of interest across biology, agriculture, or medicine. 
    more » « less