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    Glucose Transport in Cultured Animal Cells: An Exercise for the Undergraduate Cell Biology Laboratory

    Abstract

    Membrane transport is a fundamental concept that undergraduate students of cell biology understand better with laboratory experience. Formal teaching exercises commonly used to illustrate this concept are unbiological, qualitative, or intricate and time consuming to prepare. We have developed an exercise that uses uptake of radiolabeled nutrient analogues by attachment-dependent animal cells cultured on multiwell trays. This system can readily be manipulated within a typical 3-h laboratory period to yield reproducible, biologically relevant, quantitative data regarding key aspects of membrane transport. Each 24-well tray of cultures allows a group of two to four students to compare eight conditions in triplicate. If different groups of students test different conditions or different types of cells, data can be shared for an even broader experience. The exercise is also readily adaptable for open-ended student projects. Here we illustrate the exercise measuring uptake of the nonmetabolizable glucose analogue [3H]-2-deoxy-d-glucose. Students successfully tested the effects of competing sugars, putative inhibitors of the GLUT1 transporter, and changes in cell physiology that might be expected to affect glucose transport in epithelial cells and fibroblasts. In this exercise students find the nutritional and medical implications of glucose transport and its regulation intriguing. They also learn to handle radioisotopes and cultured cells.

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    Learning How Scientists Work: Experiential Research Projects to Promote Cell Biology Learning and Scientific Process Skills

    Abstract

    Facilitating not only the mastery of sophisticated subject matter, but also the development of process skills is an ongoing challenge in teaching any introductory undergraduate course. To accomplish this goal in a sophomore-level introductory cell biology course, I require students to work in groups and complete several mock experiential research projects that imitate the professional activities of the scientific community. I designed these projects as a way to promote process skill development within content-rich pedagogy and to connect text-based and laboratory-based learning with the world of contemporary research. First, students become familiar with one primary article from a leading peer-reviewed journal, which they discuss by means of PowerPoint-based journal clubs and journalism reports highlighting public relevance. Second, relying mostly on primary articles, they investigate the molecular basis of a disease, compose reviews for an in-house journal, and present seminars in a public symposium. Last, students author primary articles detailing investigative experiments conducted in the lab. This curriculum has been successful in both quarter-based and semester-based institutions. Student attitudes toward their learning were assessed quantitatively with course surveys. Students consistently reported that these projects significantly lowered barriers to primary literature, improved research-associated skills, strengthened traditional pedagogy, and helped accomplish course objectives. Such approaches are widely suited for instructors seeking to integrate process with content in their courses.

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    Cancer Cell Biology: A Student-Centered Instructional Module Exploring the Use of Multimedia to Enrich Interactive, Constructivist Learning of Science

    Abstract

    Multimedia has the potential of providing bioscience education novel learning environments and pedagogy applications to foster student interest, involve students in the research process, advance critical thinking/problem-solving skills, and develop conceptual understanding of biological topics. Cancer Cell Biology, an interactive, multimedia, problem-based module, focuses on how mutations in protooncogenes and tumor suppressor genes can lead to uncontrolled cell proliferation by engaging students as research scientists/physicians with the task of diagnosing the molecular basis of tumor growth for a group of patients. The process of constructing the module, which was guided by scientist and student feedback/responses, is described. The completed module and insights gained from its development are presented as a potential “multimedia pedagogy” for the development of other multimedia science learning environments.

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    Evaluation of Two CD-ROMs from a Series on Cell Biology

    Abstract

    Two CD-ROMs from a series dealing with various major aspects of cell biology are evaluated in this paper using quantitative and qualitative approaches. The findings delimit similarities and differences of the two CD-ROMs and shed light on how the programs could be used in the learning process and how they should not be. The overall impression, as well as the graphical and technical features, received a predominantly good rating. The defined target groups were reached (e.g., students in secondary schools), different learning approaches were supported (e.g., discovery and autonomous learning), the CD-ROMs' usability was assessed as being easy and intuitive, and the majority of the evaluators were satisfied with the level of interactivity. Navigational problems encountered in CD-ROM 1 were overcome by a successful implementation of new navigational functions in CD-ROM 2. Most students found the CD-ROM to be a suitable complement to, or an extension of, their lessons. We conclude that many, but not all of the requirements for the various stages of the learning process could be satisfied with the existing CD-ROMs. The requirements not met are discussed to obtain insights that could help to improve the production of multimedia learning material. The use of quantitative and qualitative approaches in the evaluation of learning modules is discussed, as the study began by collecting and analyzing anecdotal reviews and was then extended to include a qualitative evaluation.

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    Design and Performance Frameworks for Constructing Problem-Solving Simulations

    Abstract

    Rapid advancements in hardware, software, and connectivity are helping to shorten the times needed to develop computer simulations for science education. These advancements, however, have not been accompanied by corresponding theories of how best to design and use these technologies for teaching, learning, and testing. Such design frameworks ideally would be guided less by the strengths/limitations of the presentation media and more by cognitive analyses detailing the goals of the tasks, the needs and abilities of students, and the resulting decision outcomes needed by different audiences. This article describes a problem-solving environment and associated theoretical framework for investigating how students select and use strategies as they solve complex science problems. A framework is first described for designing on-line problem spaces that highlights issues of content, scale, cognitive complexity, and constraints. While this framework was originally designed for medical education, it has proven robust and has been successfully applied to learning environments from elementary school through medical school. Next, a similar framework is detailed for collecting student performance and progress data that can provide evidence of students' strategic thinking and that could potentially be used to accelerate student progress. Finally, experimental validation data are presented that link strategy selection and use with other metrics of scientific reasoning and student achievement.

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    Mystery of the Toxic Flea Dip: An Interactive Approach to Teaching Aerobic Cellular Respiration

    Abstract

    We designed an interrupted case study to teach aerobic cellular respiration to major and nonmajor biology students. The case is based loosely on a real-life incident of rotenone poisoning. It places students in the role of a coroner who must determine the cause of death of the victim. The case is presented to the students in four parts. Each part is followed by discussion questions that the students answer in small groups prior to a classwide discussion. Successive parts of the case provide additional clues to the mystery and help the students focus on the physiological processes involved in aerobic respiration. Students learn the information required to solve the mystery by reading the course textbook prior to class, listening to short lectures interspersed throughout the case, and discussing the case in small groups. The case ends with small group discussions in which the students are given the names and specific molecular targets of other poisons of aerobic respiration and asked to determine which process (i.e., glycolysis, citric acid cycle, or the electron transport chain) the toxin disrupts.

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    Investigations of Protein Structure and Function Using the Scientific Literature: An Assignment for an Undergraduate Cell Physiology Course

    Abstract

    Undergraduate biology curricula are being modified to model and teach the activities of scientists better. The assignment described here, one that investigates protein structure and function, was designed for use in a sophomore-level cell physiology course at Earlham College. Students work in small groups to read and present in poster format on the content of a single research article reporting on the structure and/or function of a protein. Goals of the assignment include highlighting the interdependence of protein structure and function; asking students to review, integrate, and apply previously acquired knowledge; and helping students see protein structure/function in a context larger than cell physiology. The assignment also is designed to build skills in reading scientific literature, oral and written communication, and collaboration among peers. Assessment of student perceptions of the assignment in two separate offerings indicates that the project successfully achieves these goals. Data specifically show that students relied heavily on their peers to understand their article. The assignment was also shown to require students to read articles more carefully than previously. In addition, the data suggest that the assignment could be modified and used successfully in other courses and at other institutions.

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    Evolving Strategies for the Incorporation of Bioinformatics Within the Undergraduate Cell Biology Curriculum

    Abstract

    Recent advances in genomics and structural biology have resulted in an unprecedented increase in biological data available from Internet-accessible databases. In order to help students effectively use this vast repository of information, undergraduate biology students at Drake University were introduced to bioinformatics software and databases in three courses, beginning with an introductory course in cell biology. The exercises and projects that were used to help students develop literacy in bioinformatics are described. In a recently offered course in bioinformatics, students developed their own simple sequence analysis tool using the Perl programming language. These experiences are described from the point of view of the instructor as well as the students. A preliminary assessment has been made of the degree to which students had developed a working knowledge of bioinformatics concepts and methods. Finally, some conclusions have been drawn from these courses that may be helpful to instructors wishing to introduce bioinformatics within the undergraduate biology curriculum.

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    Characterization of Pathogenic Human MSH2 Missense Mutations Using Yeast as a Model System: A Laboratory Course in Molecular Biology

    Abstract

    This work describes the project for an advanced undergraduate laboratory course in cell and molecular biology. One objective of the course is to teach students a variety of cellular and molecular techniques while conducting original research. A second objective is to provide instruction in science writing and data presentation by requiring comprehensive laboratory reports modeled on the primary literature. The project for the course focuses on a gene, MSH2, implicated in the most common form of inherited colorectal cancer. Msh2 is important for maintaining the fidelity of genetic material where it functions as an important component of the DNA mismatch repair machinery. The goal of the project has two parts. The first part is to create mapped missense mutation listed in the human databases in the cognate yeast MSH2 gene and to assay for defects in DNA mismatch repair. The second part of the course is directed towards understanding in what way are the variant proteins defective for mismatch repair. Protein levels are analyzed to determine if the missense alleles display decreased expression. Furthermore, the students establish whether the Msh2p variants are properly localized to the nucleus using indirect immunofluorescence and whether the altered proteins have lost their ability to interact with other subunits of the MMR complex by creating recombinant DNA molecules and employing the yeast 2-hybrid assay.

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    Relational Databases: A Transparent Framework for Encouraging Biology Students To Think Informatically

    Abstract

    We discuss how relational databases constitute an ideal framework for representing and analyzing large-scale genomic data sets in biology. As a case study, we describe a Drosophila splice-site database that we recently developed at Wesleyan University for use in research and teaching. The database stores data about splice sites computed by a custom algorithm using Drosophila cDNA transcripts and genomic DNA and supports a set of procedures for analyzing splice-site sequence space. A generic Web interface permits the execution of the procedures with a variety of parameter settings and also supports custom structured query language queries. Moreover, new analytical procedures can be added by updating special metatables in the database without altering the Web interface. The database provides a powerful setting for students to develop informatic thinking skills.

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    Computer Simulations Improve University Instructional Laboratories

    Abstract

    Laboratory classes are commonplace and essential in biology departments but can sometimes be cumbersome, unreliable, and a drain on time and resources. As university intakes increase, pressure on budgets and staff time can often lead to reduction in practical class provision. Frequently, the ability to use laboratory equipment, mix solutions, and manipulate test animals are essential learning outcomes, and “wet” laboratory classes are thus appropriate. In others, however, interpretation and manipulation of the data are the primary learning outcomes, and here, computer-based simulations can provide a cheaper, easier, and less time- and labor-intensive alternative. We report the evaluation of two computer-based simulations of practical exercises: the first in chromosome analysis, the second in bioinformatics. Simulations can provide significant time savings to students (by a factor of four in our first case study) without affecting learning, as measured by performance in assessment. Moreover, under certain circumstances, performance can be improved by the use of simulations (by 7% in our second case study). We concluded that the introduction of these simulations can significantly enhance student learning where consideration of the learning outcomes indicates that it might be appropriate. In addition, they can offer significant benefits to teaching staff.

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    An Inquiry into Protein Structure and Genetic Disease: Introducing Undergraduates to Bioinformatics in a Large Introductory Course

    Abstract

    This inquiry-based lab is designed around genetic diseases with a focus on protein structure and function. To allow students to work on their own investigatory projects, 10 projects on 10 different proteins were developed. Students are grouped in sections of 20 and work in pairs on each of the projects. To begin their investigation, students are given a cDNA sequence that translates into a human protein with a single mutation. Each case results in a genetic disease that has been studied and recorded in the Online Mendelian Inheritance in Man (OMIM) database. Students use bioinformatics tools to investigate their proteins and form a hypothesis for the effect of the mutation on protein function. They are also asked to predict the impact of the mutation on human physiology and present their findings in the form of an oral report. Over five laboratory sessions, students use tools on the National Center for Biotechnology Information (NCBI) Web site (BLAST, LocusLink, OMIM, GenBank, and PubMed) as well as ExPasy, Protein Data Bank, ClustalW, the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, and the structure-viewing program DeepView. Assessment results showed that students gained an understanding of the Web-based databases and tools and enjoyed the investigatory nature of the lab.

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    Survey of Undergraduate Research Experiences (SURE): First Findings

    Abstract

    In this study, I examined the hypothesis that undergraduate research enhances the educational experience of science undergraduates, attracts and retains talented students to careers in science, and acts as a pathway for minority students into science careers. Undergraduates from 41 institutions participated in an online survey on the benefits of undergraduate research experiences. Participants indicated gains on 20 potential benefits and reported on career plans. Over 83% of 1,135 participants began or continued to plan for postgraduate education in the sciences. A group of 51 students who discontinued their plans for postgraduate science education reported significantly lower gains than continuing students. Women and men reported similar levels of benefits and similar patterns of career plans. Ethnic groups did not significantly differ in reported levels of benefits or plans to continue with postgraduate education.

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    Developing Information Fluency in Introductory Biology Students in the Context of an Investigative Laboratory

    Abstract

    Students of biology must learn the scientific method for generating information in the field. Concurrently, they should learn how information is reported and accessed. We developed a progressive set of exercises for the undergraduate introductory biology laboratory that combine these objectives. Pre- and postassessments of approximately 100 students suggest that increases occurred, some statistically significant, in the number of students using various library-related resources, in the numbers and confidence level of students using various technologies, and in the numbers and confidence levels of students involved in various activities related to the scientific method. Following this course, students should be better prepared for more advanced and independent study.

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    Molecular and Cellular Biology Animations: Development and Impact on Student Learning

    Abstract

    Educators often struggle when teaching cellular and molecular processes because typically they have only two-dimensional tools to teach something that plays out in four dimensions. Learning research has demonstrated that visualizing processes in three dimensions aids learning, and animations are effective visualization tools for novice learners and aid with long-term memory retention. The World Wide Web Instructional Committee at North Dakota State University has used these research results as an inspiration to develop a suite of high-quality animations of molecular and cellular processes. Currently, these animations represent transcription, translation, bacterial gene expression, messenger RNA (mRNA) processing, mRNA splicing, protein transport into an organelle, the electron transport chain, and the use of a biological gradient to drive adenosine triphosphate synthesis. These animations are integrated with an educational module that consists of First Look and Advanced Look components that feature captioned stills from the animation representing the key steps in the processes at varying levels of complexity. These animation-based educational modules are available via the World Wide Web at http://vcell.ndsu.edu/animations. An in-class research experiment demonstrated that student retention of content material was significantly better when students received a lecture coupled with the animations and then used the animation as an individual study activity.

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    How Effective Are Simulated Molecular-level Experiments for Teaching Diffusion and Osmosis?

    Abstract

    Diffusion and osmosis are central concepts in biology, both at the cellular and organ levels. They are presented several times throughout most introductory biology textbooks (e.g., Freeman, 2002), yet both processes are often difficult for students to understand (Odom, 1995; Zuckerman, 1994; Sanger et al., 2001; and results herein). Students have deep-rooted misconceptions about how diffusion and osmosis work, especially at the molecular level. We hypothesized that this might be in part due to the inability to see and explore these processes at the molecular level. In order to investigate this, we developed new software, OsmoBeaker, which allows students to perform inquiry-based experiments at the molecular level. Here we show that these simulated laboratories do indeed teach diffusion and osmosis and help overcome some, but not all, student misconceptions.

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    An Inexpensive Gel Electrophoresis-Based Polymerase Chain Reaction Method for Quantifying mRNA Levels

    Abstract

    In order to engage their students in a core methodology of the new genomics era, an everincreasing number of faculty at primarily undergraduate institutions are gaining access to microarray technology. Their students are conducting successful microarray experiments designed to address a variety of interesting questions. A next step in these teaching and research laboratory projects is often validation of the microarray data for individual selected genes. In the research community, this usually involves the use of real-time polymerase chain reaction (PCR), a technology that requires instrumentation and reagents that are prohibitively expensive for most undergraduate institutions. The results of a survey of faculty teaching undergraduates in classroom and research settings indicate a clear need for an alternative approach. We sought to develop an inexpensive and student-friendly gel electrophoresis-based PCR method for quantifying messenger RNA (mRNA) levels using undergraduate researchers as models for students in teaching and research laboratories. We compared the results for three selected genes measured by microarray analysis, real-time PCR, and the gel electrophoresis-based method. The data support the use of the gel electrophoresis-based method as an inexpensive, convenient, yet reliable alternative for quantifying mRNA levels in undergraduate laboratories.

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    Using a Module-based Laboratory To Incorporate Inquiry into a Large Cell Biology Course

    Abstract

    Because cell biology has rapidly increased in breadth and depth, instructors are challenged not only to provide undergraduate science students with a strong, up-to-date foundation of knowledge, but also to engage them in the scientific process. To these ends, revision of the Cell Biology Lab course at the University of Wisconsin-La Crosse was undertaken to allow student involvement in experimental design, emphasize data collection and analysis, make connections to the “big picture,” and increase student interest in the field. Multiweek laboratory modules were developed as a method to establish an inquiry-based learning environment. Each module utilizes relevant techniques to investigate one or more questions within the context of a fictional story, and there is a progression during the semester from more instructor-guided to more open-ended student investigation. An assessment tool was developed to evaluate student attitudes regarding their lab experience. Analysis of five semesters of data strongly supports the module format as a successful model for inquiry education by increasing student interest and improving attitude toward learning. In addition, student performance on inquiry-based assignments improved over the course of each semester, suggesting an improvement in inquiry-related skills.

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    Students Investigating the Antiproliferative Effects of Synthesized Drugs on Mouse Mammary Tumor Cells

    Abstract

    The potential for personalized cancer management has long intrigued experienced researchers as well as the naïve student intern. Personalized cancer treatments based on a tumor's genetic profile are now feasible and can reveal both the cells' susceptibility and resistance to chemotherapeutic agents. In a weeklong laboratory investigation that mirrors current cancer research, undergraduate and advanced high school students determine the efficacy of common pharmacological agents through in vitro testing. Using mouse mammary tumor cell cultures treated with “unknown” drugs historically recommended for breast cancer treatment, students are introduced to common molecular biology techniques from in vitro cell culture to fluorescence microscopy. Student understanding is assessed through laboratory reports and the successful identification of the unknown drug. The sequence of doing the experiment, applying logic, and constructing a hypothesis gives the students time to discover the rationale behind the cellular drug resistance assay. The breast cancer experiment has been field tested during the past 5 yr with more than 200 precollege/undergraduate interns through the Gains in the Education of Mathematics and Science program hosted by the Walter Reed Army Institute of Research.

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    Teaching Systems Biology: An Active-learning Approach

    Abstract

    With genomics well established in modern molecular biology, recent studies have sought to further the discipline by integrating complementary methodologies into a holistic depiction of the molecular mechanisms underpinning cell function. This genomic subdiscipline, loosely termed“ systems biology,” presents the biology educator with both opportunities and obstacles: The benefit of exposing students to this cutting-edge scientific methodology is manifest, yet how does one convey the breadth and advantage of systems biology while still engaging the student? Here, I describe an active-learning approach to the presentation of systems biology. In graduate classes at the University of Michigan, Ann Arbor, I divided students into small groups and asked each group to interpret a sample data set (e.g., microarray data, two-hybrid data, homology-search results) describing a hypothetical signaling pathway. Mimicking realistic experimental results, each data set revealed a portion of this pathway; however, students were only able to reconstruct the full pathway by integrating all data sets, thereby exemplifying the utility in a systems biology approach. Student response to this cooperative exercise was extremely positive. In total, this approach provides an effective introduction to systems biology appropriate for students at both the undergraduate and graduate levels.