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1.
CBE Life Sci Educ ; 23(1): fe1, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38100317

RESUMO

Graphs are ubiquitous tools in science that allow one to explore data patterns, design studies, communicate findings, and make claims. This essay is a companion to the online, evidence-based interactive guide intended to help inform instructors' decision-making in how to teach graph reading, interpretation, construction, and evaluation within the discipline of biology. We provide a framework with a focus on six instructional practices that instructors can utilize when designing graphing activities: use data to engage students, teach graphing grounded in the discipline, practice explicit instruction, use real world "messy" data, utilize collaborative work, and emphasize reflection. Each component of this guide is supported by summaries of and links to articles that can inform graphing practices. The guide also contains an instructor checklist that summarizes key points with actionable steps that can guide instructors as they work towards refining and incorporating graphing into their classroom practice and emerging questions in which further empirical studies are warranted.


Assuntos
Aptidão , Recursos Audiovisuais , Visualização de Dados , Estudantes , Humanos , Leitura , Ensino , Interpretação Estatística de Dados , Compreensão
2.
CBE Life Sci Educ ; 22(4): ar44, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37751503

RESUMO

Explaining biological phenomena requires understanding how different processes function and describing interactions between components at various levels of organization over time and space in biological systems. This is a desired competency yet is a complicated and often challenging task for undergraduate biology students. Therefore, we need a better understanding of their integrated knowledge regarding important biological concepts. Informed by the theory of knowledge integration and mechanistic reasoning, in this qualitative case study, we elicited and characterized knowledge networks of nine undergraduate biology students. We investigated students' conceptions of and the various ways they connect three fundamental subsystems in biology: 1) gene regulation, 2) cell-cell communication, and 3) phenotypic expression. We found that only half of the conceptual questions regarding the three subsystems were answered correctly by the majority of students. Knowledge networks tended to be linear and unidirectional, with little variation in the types of relationships displayed. Students did not spontaneously express mechanistic connections, mainly described undefined, cellular, and macromolecular levels of organization, and mainly discussed unspecified and intracellular localizations. These results emphasize the need to support students' understanding of fundamental concepts, and promoting knowledge integration in the classroom could assist students' ability to understand biological systems.


Assuntos
Comunicação Celular , Estudantes , Humanos , Fenótipo , Conhecimento , Biologia
3.
J Microbiol Biol Educ ; 24(2)2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37614873

RESUMO

Understanding molecular processes and coordinating the various activities across levels of organization in biological systems is a complicated task, yet many curricular guidelines indicate that undergraduate students should master it. Employing mechanistic reasoning can facilitate describing and investigating biological phenomena. Biofilms are an important system in microbiology and biology education. However, few empirical studies have been conducted on student learning of biofilms or how students utilize mechanistic reasoning related to systems thinking to explain biofilm formation. Using mechanistic reasoning and the theory of knowledge integration as conceptual and analytical frameworks, we examined the features of 9 undergraduate biology students' mechanistic models of a specific transition point in biofilm development. From these data, we constructed a model of knowledge integration in the context of biofilms, which categorizes students' knowledge based on features of their descriptions (e.g., entities, correct connections, and the nature of connections). We found that 4 of 9 students produced a fragmented model, 4 of 9 students produced a transitional model, and 1 student produced a connected model. Overall, students often did not discuss cell-cell communication mechanics in their mechanistic models and rarely included the role of gene regulation. Most connections were considered nonnormative and lacked important entities, leading to an abundance of unspecified causal connections. We recommend increasing instructional support of mechanistic reasoning within systems (e.g., identifying entities across levels of organization and their relevant activities) and creating opportunities for students to grapple with their understanding of various biological concepts and to explore how processes interact and connect in a complex system.

4.
Sci Educ (Dordr) ; : 1-32, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37359259

RESUMO

Science educators report that students struggle with understanding, using, and evaluating the evidence underpinning scientific knowledge. However, there are not many studies focused on helping instructors address those difficulties. Here, we report on a laboratory instructor's scaffolding of students' evidentiary reasoning with and about evidence for evolutionary trees with guidance from the Conceptual Analysis of Disciplinary Evidence (CADE) framework, which links biological knowledge with epistemic considerations. To consider both domain-general and discipline-specific aspects of evidence, CADE was implemented to inform scaffolds in two ways: (1) generic evidence scaffolds (GES) reminded students of general epistemic considerations; (2) disciplinary evidence scaffolds (DES) explicitly reminded students of the disciplinary knowledge of relevance for considering biological evidence. An instructor's lab discussions were compared before and after they had a workshop with CADE. CADE helped the lab instructor facilitate students' evidentiary reasoning about evolutionary trees. In comparison to baseline, both GES and DES discussions covered more aspects and relationships among types of evidence for evolutionary tree-thinking and the instructor prompted more kinds of general epistemic considerations and biological knowledge. DES discussions emphasized the importance of disciplinary knowledge for research design. The CADE framework guided planning and implementation of intentional scaffolding aimed at guiding evidentiary reasoning. Supplementary Information: The online version contains supplementary material available at 10.1007/s11191-023-00435-6.

5.
CBE Life Sci Educ ; 19(1): ar3, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31971876

RESUMO

When a student explains a biological phenomenon, does the answer reflect only the product of retrieving knowledge or does it also reflect a dynamic process of constructing knowledge? To gain insight into students' dynamic knowledge, we leveraged three analytic frameworks-structures-behaviors-functions (SBF), mental models (MM), and conceptual dynamics (CD). To assess the stability of student knowledge, we asked undergraduate students to explain the same physiological phenomenon three times-once verbally, once after drawing, and once after interpreting a diagram. The SBF analysis illustrated fine-grained dynamic knowledge between tasks. The MM analysis suggested global stability between tasks. The CD analysis demonstrated local instability within tasks. The first two analyses call attention to differences between students' knowledge about the parts of systems and their organization. The CD analysis, however, calls attention to similar learning mechanisms that operate differently vis-à-vis external representations. Students with different mental models deliberated localization or where to locate the structures and mechanisms that mediate physiological responses, but students made these deliberations during different tasks and arrived at different conclusions. These results demonstrate the utility of incorporating dynamic approaches to complement other analytic approaches and motivate future research agendas in biology education research.


Assuntos
Conhecimento , Fisiologia , Estudantes , Humanos , Aprendizagem , Fisiologia/educação
6.
CBE Life Sci Educ ; 17(4): ar65, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30496033

RESUMO

As undergraduate biology curricula increasingly aim to provide students with access to courses and experiences that engage them in the practices of science, tools are needed for instruction, evaluation, and research around student learning. One of the important skills for undergraduate biology students to master is the selection and creation of appropriate graphs to summarize data they acquire through investigations in their course work and research experiences. Graphing is a complex skill, and there are few, discipline-informed tools available for instructors, students, and researchers to use. Here, we describe the development of a graph rubric informed by literature from the learning sciences, statistics, representations literature, and feedback and use of the rubric by a variety of users. The result is an evidence-based, analytic rubric that consists of categories essential for graph choice and construction: graph mechanics, graph communication, and graph choice. Each category of the rubric can be evaluated at three levels of achievement. Our analysis demonstrates the potential for the rubric to provide formative feedback to students and allow instructors to gauge and guide learning and instruction. We further discuss and identify potentially interesting research targets for science education researchers.


Assuntos
Aprendizagem , Pesquisa , Ensino , Biologia/educação , Currículo , Retroalimentação , Humanos , Reprodutibilidade dos Testes , Ciência/educação , Estudantes
7.
CBE Life Sci Educ ; 17(2): es2, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29749843

RESUMO

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.


Assuntos
Biologia/educação , Comportamento Cooperativo , Estudos Interdisciplinares , Características de Residência , Comunicação , Tomada de Decisões , Humanos , Conhecimento , Aprendizagem , Pesquisadores
8.
CBE Life Sci Educ ; 16(3)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28821538

RESUMO

Undergraduate biology education reform aims to engage students in scientific practices such as experimental design, experimentation, and data analysis and communication. Graphs are ubiquitous in the biological sciences, and creating effective graphical representations involves quantitative and disciplinary concepts and skills. Past studies document student difficulties with graphing within the contexts of classroom or national assessments without evaluating student reasoning. Operating under the metarepresentational competence framework, we conducted think-aloud interviews to reveal differences in reasoning and graph quality between undergraduate biology students, graduate students, and professors in a pen-and-paper graphing task. All professors planned and thought about data before graph construction. When reflecting on their graphs, professors and graduate students focused on the function of graphs and experimental design, while most undergraduate students relied on intuition and data provided in the task. Most undergraduate students meticulously plotted all data with scaled axes, while professors and some graduate students transformed the data, aligned the graph with the research question, and reflected on statistics and sample size. Differences in reasoning and approaches taken in graph choice and construction corroborate and extend previous findings and provide rich targets for undergraduate and graduate instruction.


Assuntos
Biologia/educação , Gráficos por Computador , Educação de Pós-Graduação , Avaliação Educacional , Humanos , Projetos de Pesquisa , Estudantes
9.
Adv Physiol Educ ; 41(2): 270-278, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28442480

RESUMO

Physiology demands systems thinking: reasoning within and between levels of biological organization and across different organ systems. Many physiological mechanisms explain how structures and their properties interact at one level of organization to produce emergent functions at a higher level of organization. Current physiology principles, such as structure-function relations, selectively neglect mechanisms by not mentioning this term explicitly. We explored how students characterized mechanisms and functions to shed light on how students make sense of these terms. Students characterized mechanisms as 1) processes that occur at levels of organization lower than that of functions; and 2) as detailed events with many steps involved. We also found that students produced more variability in how they characterized functions compared with mechanisms: students characterized functions in relation to multiple levels of organization and multiple definitions. We interpret these results as evidence that students see mechanisms as holding a more narrow definition than used in the biological sciences, and that students struggle to coordinate and distinguish mechanisms from functions due to cognitive processes germane to learning in many domains. We offer the instructional suggestion that we scaffold student learning by affording students opportunities to relate and also distinguish between these terms so central to understanding physiology.


Assuntos
Aprendizagem , Fisiologia/educação , Compreensão , Humanos , Estudantes , Pensamento
11.
J Microbiol Biol Educ ; 14(1): 25-34, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23858351

RESUMO

Recent recommendations for biology education highlight the role of authentic research experiences early in undergraduate education as a means of increasing the number and quality of biology majors. These experiences will inform students on the nature of science, increase their confidence in doing science, as well as foster critical thinking skills, an area that has been lacking despite it being one of the desired outcomes at undergraduate institutions and with future employers. With these things in mind, we have developed an introductory biology laboratory course where students design and execute an authentic microbiology research project. Students in this course are assimilated into the community of researchers by engaging in scholarly activities such as participating in inquiry, reading scientific literature, and communicating findings in written and oral formats. After three iterations of a semester-long laboratory course, we found that students who took the course showed a significant increase in their understanding of the nature of authentic research and their level of critical thinking skills.

12.
Artigo em Inglês | MEDLINE | ID: mdl-23129994

RESUMO

The inferior colliculus (IC) receives ascending excitatory and inhibitory inputs from multiple sources, but how these auditory inputs converge to generate IC spike patterns is poorly understood. Simulating patterns of in vivo spike train data from cellular and synaptic models creates a powerful framework to identify factors that contribute to changes in IC responses, such as those resulting in age-related loss of temporal processing. A conductance-based single neuron IC model was constructed, and its responses were compared to those observed during in vivo IC recordings in rats. IC spike patterns were evoked using amplitude-modulated tone or noise carriers at 20-40 dB above threshold and were classified as low-pass, band-pass, band-reject, all-pass, or complex based on their rate modulation transfer function tuning shape. Their temporal modulation transfer functions were also measured. These spike patterns provided experimental measures of rate, vector strength, and firing pattern for comparison with model outputs. Patterns of excitatory and inhibitory synaptic convergence to IC neurons were based on anatomical studies and generalized input tuning for modulation frequency. Responses of modeled ascending inputs were derived from experimental data from previous studies. Adapting and sustained IC intrinsic models were created, with adaptation created via calcium-activated potassium currents. Short-term synaptic plasticity was incorporated into the model in the form of synaptic depression, which was shown to have a substantial effect on the magnitude and time course of the IC response. The most commonly observed IC response sub-types were recreated and enabled dissociation of inherited response properties from those that were generated in IC. Furthermore, the model was used to make predictions about the consequences of reduction in inhibition for age-related loss of temporal processing due to a reduction in GABA seen anatomically with age.

14.
DNA Cell Biol ; 31(6): 956-67, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22360681

RESUMO

In Enterobacteriaceae, the ProP protein, which takes up proline and glycine betaine, is subject to a post-translational control mechanism that increases its activity at high osmolarity. In order to investigate the osmoregulatory mechanism of the Salmonella enterica ProP, we devised a positive selection for mutations that conferred increased activity on this protein at low osmolarity. The selection involved the isolation of mutations in a proline auxotroph that resulted in increased accumulation of proline via the ProP system in the presence of glycine betaine, which is a competitive inhibitor of proline uptake by this permease. This selection was performed by first-year undergraduates in two semesters of a research-based laboratory course. The students generated sixteen mutations resulting in six different single amino acids substitutions. They determined the effects of the mutations on the growth rates of the cells in media of high and low osmolarity in the presence of low concentrations of proline or glycine betaine. Furthermore, they identified the mutations by DNA sequencing and displayed the mutated amino acids on a putative three-dimensional structure of the protein. This analysis suggested that all six amino acid substitutions are residues in trans-membrane helices that have been proposed to contribute to the formation of the transport pore, and, thus, may affect the substrate binding site of the protein.


Assuntos
Substituição de Aminoácidos , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Mutação de Sentido Incorreto , Engenharia de Proteínas/métodos , Salmonella typhimurium/metabolismo , Equilíbrio Hidroeletrolítico/genética , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Modelos Moleculares , Dados de Sequência Molecular , Fenótipo , Prolina , Conformação Proteica , Salmonella typhimurium/genética , Salmonella typhimurium/crescimento & desenvolvimento
15.
Am J Med Genet A ; 155A(6): 1367-73, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21567905

RESUMO

Nonhuman primates have been a common animal model to evaluate experimentally induced malformations. Reports on spontaneous malformations are important in determining the background incidence of congenital anomalies in specific species and in evaluating experimental results. Here we report on a stillborn cynomolgus monkey (Macaca fascicularis) with multiple congenital anomalies from the colony maintained at the Southwest National Primate Research Center at the Texas Biomedical Research Institute, San Antonio, Texas. Physical findings included low birth weight, craniorachischisis, facial abnormalities, omphalocele, malrotation of the gut with areas of atresia and intussusception, a Meckel diverticulum, arthrogryposis, patent ductus arteriosus, and patent foramen ovale. The macaque had normal male external genitalia, but undescended testes. Gestational age was unknown but was estimated from measurements of the limbs and other developmental criteria. Although cytogenetic analysis was not possible due to the tissues being in an advanced state of decomposition, array Comparative Genomic Hybridization analysis using human bacterial artificial chromosome clones was successful in effectively eliminating aneuploidy or any copy number changes greater than approximately 3-5 Mb as a cause of the malformations. Further evaluation of the animal included extensive imaging of the skeletal and neural tissue defects. The animal's congenital anomalies are discussed in relation to the current hypotheses attempting to explain the frequent association of neural tube defects with other abnormalities.


Assuntos
Hérnia Umbilical/veterinária , Macaca fascicularis/anormalidades , Macaca fascicularis/genética , Defeitos do Tubo Neural/veterinária , Animais , Hibridização Genômica Comparativa , Análise Citogenética , Hérnia Umbilical/genética , Hérnia Umbilical/patologia , Imageamento por Ressonância Magnética , Masculino , Defeitos do Tubo Neural/genética , Defeitos do Tubo Neural/patologia , Natimorto/veterinária , Microtomografia por Raio-X
16.
J Undergrad Neurosci Educ ; 10(1): A24-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23626490

RESUMO

Inquiry-based laboratory instruction has been shown to actively engage students in the content and skills being taught. These courses are further intended to teach students not only what is known, but also the process by which investigators come to know it. We sought to take this approach one step further and incorporate novel research questions into an inquiry-based laboratory model early in the undergraduate course of study. In this research-based introductory laboratory course, first-year students acquired basic lab skills not just for their own sake, but rather within the context of a research question of a member of the faculty. Student projects investigated potential neuroanatomical changes in animal models of dyslexia and aging and included measurements of neuron numbers and levels and distribution of neuronal proteins. Students played an active role in designing and implementing an experimental plan, explored data analysis techniques, and reflected on the results that they obtained in scholarly forms such as research papers and a departmental poster session. Student feedback on this approach has been extremely positive, and the data collected were research quality preliminary data that are being actively pursued for further study. Based on our encouraging experiences, we conclude that designing an introductory course around novel research, including some assessments modeled after scholarly practices, provides motivation and excitement for the students, instills good scientific habits, and can potentially benefit departmental research.

17.
Neuron ; 45(6): 903-15, 2005 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-15797551

RESUMO

A recently described form of synaptic plasticity results in dynamic changes in the calcium permeability of synaptic AMPA receptors. Since the AMPA receptor GluR2 subunit confers calcium permeability, this plasticity is thought to occur through the dynamic exchange of synaptic GluR2-lacking and GluR2-containing receptors. To investigate the molecular mechanisms underlying this calcium-permeable AMPA receptor plasticity (CARP), we examined whether AMPA receptor exchange was mediated by subunit-specific protein-protein interactions. We found that two GluR2-interacting proteins, the PDZ domain-containing Protein interacting with C kinase (PICK1) and N-ethylmaleimide sensitive fusion protein (NSF), are specifically required for CARP. Furthermore, PICK1, but not NSF, regulates the formation of extrasynaptic plasma membrane pools of GluR2-containing receptors that may be laterally mobilized into synapses during CARP. These results demonstrate that PICK1 and NSF dynamically regulate the synaptic delivery of GluR2-containing receptors during CARP and thus regulate the calcium permeability of AMPA receptors at excitatory synapses.


Assuntos
Canais de Cálcio/metabolismo , Proteínas de Transporte/metabolismo , Plasticidade Neuronal/fisiologia , Proteínas Nucleares/metabolismo , Receptores de AMPA/metabolismo , Sinapses/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Cálcio/metabolismo , Sinalização do Cálcio/fisiologia , Proteínas de Transporte/genética , Proteínas de Ciclo Celular , Membrana Celular/metabolismo , Permeabilidade da Membrana Celular/fisiologia , Proteínas do Citoesqueleto , Dinaminas/metabolismo , Endocitose/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Proteínas Sensíveis a N-Etilmaleimida , Proteínas Nucleares/genética , Técnicas de Cultura de Órgãos , Técnicas de Patch-Clamp , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Transporte Proteico/fisiologia , Ratos , Ratos Sprague-Dawley , Agregação de Receptores/fisiologia , Receptores de AMPA/genética
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