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Visual literacy, which is the ability to effectively identify, interpret, evaluate, use, and create images and visual media, is an important aspect of science literacy. As molecular processes are not directly observable, researchers and educators rely on visual representations (e.g., drawings) to communicate ideas in biology. How learners interpret and organize those numerous diagrams is related to their underlying knowledge about biology and their skills in visual literacy. Furthermore, it is not always obvious how and why learners interpret diagrams in the way they do (especially if their interpretations are unexpected), as it is not possible to "see" inside the minds of learners and directly observe the inner workings of their brains. Hence, tools that allow for the investigation of visual literacy are needed. Here, we present a novel card-sorting task based on visual literacy skills to investigate how learners interpret and think about DNA-based concepts. We quantified differences in performance between groups of varying expertise and in pre- and postcourse settings using percentages of expected card pairings and edit distance to a perfect sort. Overall, we found that biology experts organized the visual representations based on deep conceptual features, while biology learners (novices) more often organized based on surface features, such as color and style. We also found that students performed better on the task after a course in which molecular biology concepts were taught, suggesting the activity is a useful and valid tool for measuring knowledge. We have provided the cards to the community for use as a classroom activity, as an assessment instrument, and/or as a useful research tool to probe student ideas about molecular biology.

Learning molecular biology involves using visual representations to communicate ideas about largely unobservable biological processes and molecules. Genes and gene expression cannot be directly visualized, but students are expected to learn and understand these and related concepts. Theoretically, textbook illustrations should help learners master such concepts, but how are genes and other DNA-linked concepts illustrated for learners? We examined all DNA-related images found in 12 undergraduate biology textbooks to better understand what biology students encounter when learning concepts related to DNA. Our analysis revealed a wide array of DNA images that were used to design a new visual framework, the DNA Landscape, which we applied to more than 2000 images from common introductory and advanced biology textbooks. All DNA illustrations could be placed on the landscape framework, but certain positions were more common than others. We mapped figures about "gene expression" and "meiosis" onto the landscape framework to explore how these challenging topics are illustrated for learners, aligning these outcomes with the research literature to showcase how the overuse of certain representations may hinder, instead of help, learning. The DNA Landscape is a tool to promote research on visual literacy and to guide new learning activities for molecular biology.

Many biology students struggle to learn about the process of meiosis and have particular difficulty understanding the molecular basis of crossing over and the importance of homologous pairing for proper segregation. To help students overcome these challenges, we designed an activity that uses a newly developed Chromosome Connections Kit® from 3-D Molecular Designs to allow learners to explore meiosis at the molecular level. We took a backwards design approach in constructing an effective classroom activity. We developed evidence-based learning objectives and designed a crossing over activity that targets students' misconceptions and key concepts about meiosis. Assessment questions were designed based on the learning objectives and common student misconceptions. The activity consists of three parts: an interactive introductory video, a model-based activity, and reflection questions. The activity was first beta-tested with a small number of students and revised based on feedback. The revised activity was deployed in a mid-level Cell and Molecular Biology course. Analysis of pre-/post-assessment data from students who completed the activity (n = 83) showed strong learning gains on concepts related to ploidy, homology, segregation, and the mechanism and purpose of crossing over. Additionally, students who participated in the activity outperformed nonparticipants on a Genetics assessment about meiosis the following semester.

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.

The typical "flipped classroom" delivers lecture material in video format to students outside of class in order to make space for active learning in class. But why give students passive material at all? We are developing a set of high-quality online educational materials that promote active, hands-on science learning to aid in teaching of core concepts for introductory biology at the college level. Interactive video vignettes (IVVs) incorporate evidence-based teaching strategies to address known areas of confusion for entering students. Each IVV includes a live-action scenario with undergraduates investigating a biological problem with a realistic experiment that users participate in. Through the course of each 10-20 minute video, users are required to make predictions, answer questions, collect data and draw conclusions. Branching and reflection of previous answers allows each user to have a personalized experience. Research into how students learn with these tools is being used to develop entire modules that will incorporate the IVV as a priming activity to be done as homework, along with suggested activities to be done in class that take the introduced concepts deeper and/or broader.

The process of meiosis is an essential topic that secondary and postsecondary students struggle with. The important meiosis-related concepts of homology, ploidy, and segregation can be described using the DNA Triangle framework, which connects them to the multidimensional nature of DNA (chromosomal, molecular, and informational levels). We have previously established that undergraduate biology students typically fail to describe and/or link appropriate levels to their explanations of meiosis. We hypothesize that students' understanding mirrors the resources they are given -- in other words, textbook figures often lack many of the important connections that experts include when talking about meiosis. Prior work showed that text in meiosis chapters typically fails to include many concepts that experts consider important, so we examined how textbook figures present meiosis concepts. We found that almost all textbook representations include the chromosomal level of DNA, but few include the other levels, even to illustrate concepts that are rooted in informational and/or molecular levels. In particular, the molecular level of DNA was absent from nearly all introductory textbook figures examined, and the informational level was seldom depicted in mid/upper-level textbook figures. The previously established deficits in text portions of textbooks are clearly not compensated by their accompanying illustrations.

Since 2009, the U.S. National Science Foundation Directorate for Biological Sciences has funded Research Coordination Networks (RCN) aimed at collaborative efforts to improve participation, learning, and assessment in undergraduate biology education (UBE). RCN-UBE projects focus on coordination and communication among scientists and educators who are fostering improved and innovative approaches to biology education. When faculty members collaborate with the overarching goal of advancing undergraduate biology education, there is a need to optimize collaboration between participants in order to deeply integrate the knowledge across disciplinary boundaries. In this essay we propose a novel guiding framework for bringing colleagues together to advance knowledge and its integration across disciplines, the "Five 'C's' of Collaboration: Commitment, Collegiality, Communication, Consensus, and Continuity." This guiding framework for professional network practice is informed by both relevant literature and empirical evidence from community-building experience within the RCN-UBE Advancing Competencies in Experimentation-Biology (ACE-Bio) Network. The framework is presented with practical examples to illustrate how it might be used to enhance collaboration between new and existing participants in the ACE-Bio Network as well as within other interdisciplinary networks.

In this article, we begin to unpack the phenomenon of representational competence by exploring how arrow symbols are used in introductory biology textbook figures. Out of 1214 figures in an introductory biology textbook, 632 (52%) of them contained arrows that were used to represent many different concepts or processes. Analysis of these figures revealed little correlation between arrow style and meaning. A more focused study of 86 figures containing 230 arrows from a second textbook showed the same pattern of inconsistency. Interviews with undergraduates confirmed that arrows in selected textbook figures were confusing and did not readily convey the information intended by the authors. We also present findings from an online survey in which subjects were asked to infer meaning of different styles of arrows in the absence of context. Few arrow styles had intrinsic meaning to participants, and illustrators did not always use those arrows for the meanings expected by students. Thus, certain styles of arrows triggered confusion and/or incorrect conceptual ideas. We argue that (1) illustrators need to be more clear and consistent when using arrow symbols, (2) instructors need to be cognizant of the level of clarity of representations used during instruction, and (3) instructors should help students learn how to interpret representations containing arrows.

The essence of molecular biology education lies in understanding of gene expression, with subtopics including the central dogma processes, such as transcription and translation. While these concepts are core to the discipline, they are also notoriously difficult for students to learn, probably because they cannot be directly observed. While nearly all active learning strategies have been shown to improve learning compared with passive lectures, little has been done to compare different types of active learning. We hypothesized that physical models of central dogma processes would be especially helpful for learning, because they provide a resource that students can see, touch, and manipulate while trying to build their knowledge. For students enrolled in an entirely active-learning-based Cell & Molecular Biology course, we examined whether model-based activities were more effective than non-model based activities. To test their understanding at the beginning and end of the semester, we employed the multiple-select Central Dogma Concept Inventory (CDCI). Each student acted as their own control, as all students engaged in all lessons yet some questions related to model-based activities and some related to clicker questions, group problem-solving, and other non-model-based activities. While all students demonstrated learning gains on both types of question, they showed much higher learning gains on model-based questions. Examining their selected answers in detail showed that while higher performing students were prompted to refine their already-good mental models to be even better, lower performing students were able to construct new knowledge that was much more consistent with an expert's understanding.

Although instruction on meiosis is repeated many times during the undergraduate curriculum, many students show poor comprehension even as upper-level biology majors. We propose that the difficulty lies in the complexity of understanding DNA, which we explain through a new model, the DNA triangle. The "DNA triangle" integrates three distinct scales at which one can think about DNA: "chromosomal," "molecular," and "informational." Through analysis of interview and survey data from biology faculty and students through the lens of the DNA triangle, we illustrate important differences in how novices and experts are able to explain the concepts of "ploidy," "homology," and "mechanism of homologous pairing." Similarly, analysis of passages from 16 different biology textbooks shows a large divide between introductory and advanced material, with introductory books omitting explanations of meiosis-linked concepts at the "molecular" level of DNA. Finally, backed by textbook findings and feedback from biology experts, we show that the DNA triangle can be applied to teaching and learning meiosis. By applying the DNA triangle to topics on meiosis we present a new framework for educators and researchers that ties concepts of ploidy, homology, and mechanism of homologous pairing to knowledge about DNA on the chromosomal, molecular, and informational levels.

Scientific teaching requires scientifically constructed, field-tested instruments to accurately evaluate student thinking and gauge teacher effectiveness. We have developed a 23-question, multiple select--format assessment of student understanding of the essential concepts of the central dogma of molecular biology that is appropriate for all levels of undergraduate biology. Questions for the Central Dogma Concept Inventory (CDCI) tool were developed and iteratively revised based on student language and review by experts. The ability of the CDCI to discriminate between levels of understanding of the central dogma is supported by field testing (N = 54), and large-scale beta testing (N = 1733). Performance on the assessment increased with experience in biology; scores covered a broad range and showed no ceiling effect, even with senior biology majors, and pre/posttesting of a single class focused on the central dogma showed significant improvement. The multiple-select format reduces the chances of correct answers by random guessing, allows students at different levels to exhibit the extent of their knowledge, and provides deeper insight into the complexity of student thinking on each theme. To date, the CDCI is the first tool dedicated to measuring student thinking about the central dogma of molecular biology, and version 5 is ready to use.

The central dogma of molecular biology, a model that has remained intact for decades, describes the transfer of genetic information from DNA to protein though an RNA intermediate. While recent work has illustrated many exceptions to the central dogma, it is still a common model used to describe and study the relationship between genes and protein products. We investigated understanding of central dogma concepts and found that students are not primed to think about information when presented with the canonical figure of the central dogma. We also uncovered conceptual errors in student interpretation of the meaning of the transcription arrow in the central dogma representation; 36% of students (n = 128; all undergraduate levels) described transcription as a chemical conversion of DNA into RNA or suggested that RNA existed before the process of transcription began. Interviews confirm that students with weak conceptual understanding of information flow find inappropriate meaning in the canonical representation of central dogma. Therefore, we suggest that use of this representation during instruction can be counterproductive unless educators are explicit about the underlying meaning.

Cellular processes that rely on knowledge of molecular behavior are difficult for students to comprehend. For example, thorough understanding of meiosis requires students to integrate several complex concepts related to chromosome structure and function. Using a grounded theory approach, we have unified classroom observations, assessment data, and in-depth interviews under the theory of knowledge transfer to explain student difficulties with concepts related to chromosomal behavior. In this paper, we show that students typically understand basic chromosome structure but do not activate cognitive resources that would allow them to explain macromolecular phenomena (e.g., homologous pairing during meiosis). To improve understanding of topics related to genetic information flow, we suggest that instructors use pedagogies and activities that prime students for making connections between chromosome structure and cellular processes. (Contains 7 figures and 2 tables.)

Chromosome structure is confusing to students at all levels, and chromosome behavior during meiosis is a notoriously difficult topic. Undergraduate biology majors are exposed to the process of meiosis numerous times during their presecondary and postsecondary education, yet understanding of key concepts, such as the point at which haploidy is established, does not improve substantially with repeated exposure. Based on student's drawings, 96% of intermediate-level biology majors have unclear or incorrect ideas about meiosis. Students have difficulty diagramming the process of meiosis starting with three unreplicated pairs of chromosomes, and even when they can produce an accurate diagram, they are unclear how to assign the terms "haploid" and "diploid." We designed an interactive lesson based on constructivist theory to address these issues in a large lecture class. Pretest and posttest scores showed a significant improvement in students' understanding of ploidy compared to a parallel class taught in the traditional way ("e.g." using the textbook diagrams). In interviews afterward, those students whose scores improved on exams specifically pointed to the features of the in-class modeling that were deliberately incorporated for that purpose. (Contains 6 figures and 3 tables.)

Molecular biology can be challenging for undergraduate students because it requires visual literacy skills to interpret abstract representations of submicroscopic concepts, structures and processes. The Conceptual-Reasoning-Mode framework suggests that visual literacy relies on applying conceptual knowledge to appropriately reason with the different ways of representing concepts in molecular biology. We used this framework to specifically explore visual literacy related to chromosomes. We conducted 35 semi-structured interviews with students who had taken at least a year of college-level biology courses, and we asked them to sketch chromosomes, interpret an abstract representation of chromosomes, and use the abstract representation to answer a multiple-choice question about meiosis. While many participants used the correct vocabulary to describe chromosome structure and function, probing their visual literacy skills revealed gaps in their understanding. Notably, 97% of participants (34 of 35) held conceptual errors related to chromosome structure and function, which were often only revealed in their sketches or explanations of their sketches. Our findings highlight the importance of scaffolding visual literacy skills into instruction by teaching with a variety of visual models and engaging students in using and interpreting the conventions of abstract representations of chromosomes.