Experts in the field of molecular and cellular biology (MCB) use domain-specific reasoning strategies to navigate the unique complexities of the phenomena they study and creatively explore problems in their fields. One primary goal of instruction in undergraduate MCB is to foster the development of these domain-specific reasoning strategies among students. However, decades of evidence-based research and many national calls for undergraduate instructional reform have demonstrated that teaching and learning complex fields like MCB is difficult for instructors and learners alike. Therefore, how do students develop rich understandings of biological mechanisms? It is the aim of this dissertation work to explore features of expertise and knowledge building in undergraduate MCB by investigating knowledge organization and problem-solving strategies. Semi-structured clinical think-aloud interviews were conducted with introductory and upper-division students in MCB. Results suggest that students must sort ideas about molecular mechanism into appropriate mental categories, create connections using function-driven and mechanistic rather than associative reasoning, and create nested and overlapping ideas in order to build a nuanced network of biological ideas. Additionally, I characterize the observable components of generative multi-level mechanistic reasoning among undergraduate MCB students constructing explanations about in two novel problem-solving contexts. Results indicate that like MCB experts, students are functionally subdividing the overarching mechanism into functional modules, hypothesizing and instantiating plausible schema, and even flexibly consider the impact of mutations across ontological and biophysical levels. However "filling in" these more abstract schema with molecular mechanisms remains problematic for many students, with students instead employing a range of developing mechanistic strategies. Through this investigation of expertise and knowledge building, I characterize several of the ways in which knowledge integration and generative explanation building are productively constrained by domain-specific features, expand on several discovered barriers to productive knowledge organization and mechanistic explanation building, and suggest instructional implications for undergraduate learning.

The purpose of this study was to examine the relative effectiveness of three-dimensional visualization techniques for learning about protein conformation and molecular motion in association with a ligand and receptor binding event. Increasingly complex versions of the same binding event were depicted in each of four animated treatments. Students (n = 131) were tested at three time points, and over both the short and longer term, the most complex of the four animated treatments was the most successful at fostering students’ understanding of the events depicted. A follow-up study including eight biology students was conducted to gain greater insight into the students’ underlying thought processes and better characterize their understanding of the animated representations. Analysis of verbal reports and eye tracking data suggest that students are able to attend to the same narrative elements regardless of the level of complexity depicted in each animation. Analysis of verbal protocol data revealed a positive correlation between the number of explanatory statements expressed by participants and the complexity of the animation viewed. As well, prior knowledge was positively correlated with the number of explanatory statements contained in each protocol. Overall, students demonstrated an understanding of protein conformation and molecular crowding. However results suggest that students have difficulty understanding and associating randomness with molecular events. The verbal reports contained several instances of students’ attaching agency to protein and ligand, anthropomorphizing their movements and subsequent binding. Ordinarily cellular events, owing to their sheer complexity, are depicted in a highly schematized, simplified form. The results of this study would suggest that under select circumstances this may not be the most appropriate approach to depicting dynamic events. However additional attention must be given to exploring techniques that can satisfactorily balance the random nature of molecular events with narrative explanations of these processes.

The purpose of this study was to examine the relative effectiveness of three-dimensional visualization techniques for learning about protein conformation and molecular motion in association with a ligand and receptor binding event. Increasingly complex versions of the same binding event were depicted in each of four animated treatments. Students (n = 131) were tested at three time points, and over both the short and longer term, the most complex of the four animated treatments was the most successful at fostering students’ understanding of the events depicted. A follow-up study including eight biology students was conducted to gain greater insight into the students’ underlying thought processes and better characterize their understanding of the animated representations. Analysis of verbal reports and eye tracking data suggest that students are able to attend to the same narrative elements regardless of the level of complexity depicted in each animation. Analysis of verbal protocol data revealed a positive correlation between the number of explanatory statements expressed by participants and the complexity of the animation viewed. As well, prior knowledge was positively correlated with the number of explanatory statements contained in each protocol. Overall, students demonstrated an understanding of protein conformation and molecular crowding. However results suggest that students have difficulty understanding and associating randomness with molecular events. The verbal reports contained several instances of students’ attaching agency to protein and ligand, anthropomorphizing their movements and subsequent binding. Ordinarily cellular events, owing to their sheer complexity, are depicted in a highly schematized, simplified form. The results of this study would suggest that under select circumstances this may not be the most appropriate approach to depicting dynamic events. However additional attention must be given to exploring techniques that can satisfactorily balance the random nature of molecular events with narrative explanations of these processes.

One learning problem is that public understanding of science is limited. Many people blame at least part of the problem on the predominant lecture approach for students' lack of science understanding. Current research indicates that more active instructional approaches can improve student learning in introductory undergraduate biology courses. Active learning may be difficult to implement because methods and strategies, ranging from in-class collaborative problem-solving to out of class multimedia presentations, are diverse, and sometimes difficult to implement. Merrill's First Principles of Instruction (hereafter referred to as "First Principles" or "First Principles of Instruction") provides a framework for implementing active learning strategies. This study used First Principles of Instruction as a framework for organizing multiple active learning strategies in a web-based module in an introductory biology course. Participants in this exploratory study were university students in Life Sciences 1350, an introductory biology course for nonscience majors. Students were randomly assigned to use either the module using First Principles of Instruction (hereafter called the First Principles module) or the module using a more traditional web-based approach (hereafter called the traditional module) as supplementary instruction. The First Principles module implemented several active learning strategies and used a progression of whole problems and several demonstration and application activities to teach the topic of "microevolution," defined as the study of how populations evolve and change over time. The traditional module implemented a more traditional web-based approach, providing information and explanations about microevolution with limited examples. This exploratory study's results showed that the learning gain from pretest to posttest at the remember level was significant for the traditional group at alpha = .05 and was significant for the First Principles group at alpha = .1. In addition the pretest to posttest gain at problem solving for the First Principles group was significant at alpha = .05. When students rated their confidence in solving future problems, those in the First Principles group were significantly more likely to predict future success at alpha = .1.

This study examined an innovative, project-based curriculum in a freshman biology laboratory by focusing on how students developed their conceptual understanding of a biological species. A model for learning was posed based on learners working in small groups. This model linked a sociocultural approach to teaching and learning to conceptual change theory. Qualitative research methods were employed to collect a variety of data. Documentation of this innovative curriculum is provided. This investigative curriculum incorporated the research practices that scientists use. A wide range of dynamic interactions with students actively investigating problems and sharing both their findings and thoughts during this time occurred. This essentially modeled the authentic practices of scientists. A direct comparison was made with this learning environment and the model for learning. Peer tutoring, cooperative learning, and most importantly, peer collaboration were observed when students grappled with difficult problems for which there was no single right answer. Teachers served as guides in learning, shifting responsibility to the students. Analysis of student writing revealed richer, more complex definitions of species after the experience of the laboratory project. Several of the students used knowledge gained directly from their experiences during the laboratory project to help elaborate their definitions. The electronic discussions showed a range of social interactions and interactivity. High quality discussions were found to be rich in scientific thought, engaging discussants by offering information, questioning, and actively hypothesizing. Mediating and facilitating discussions by the participants was found to be an important factor in their success. Groups exhibiting high quality discussions also had a lower response time than other groups, indicating that more substantive dialogues which are rich in thought proceed at a slower pace. Significantly, an important connection has been made between the socio-cultural approach to learning and conceptual change theory. A closer examination of how small groups of learners develop conceptual understanding is needed. This approach also needs to be extended into other settings where reform in science education is taking place. / Ph. D.

The purpose of this study was to evaluate the undergraduate biology practical instructions and the level of competence of undergraduate biology students in practical laboratory skills in some Ethiopian universities using skill performance rubric and questionnaires. A sample of 208 third year students and 26 instructors and laboratory assistants from three universities were selected as sample of the study. Students reported that more than 84.2% of the laboratory activities are below the average number of laboratory activities recommended by the curriculum with no significant difference between universities. The laboratory skill performance test score was below the midpoint. None of the students could be able to estimate and determine fields of vision of a microscope. There is a significant and a positively linear relationship between the students’ grade point average (GPA) with identification of laboratory equipment, handling of microscope, setting of microscope, estimation of diameter of field of vision and measuring liquid. Laboratory skill performance test score is correlated with higher education entrance exam score but not with students’ high school laboratory back ground. There is no significant difference in instructor’s manipulative skills among universities (p ≥ 0.09) and instructors manipulative skills is neither correlated with qualification nor teaching experience (P≥0.056). The most common method of assessment instructors’ use in the laboratory is laboratory report and identification of specimen examination (46.4%) and written exam and identification of specimen examination (35.7%). The number of courses having laboratory manuals is as low as 14.3%, in the new university. Manipulating materials, measuring and using numbers, and pre lab activity were common activities, and were found in every manual and in every university. Moreover, the result also revealed that the manuals contain high percentage rate of basic science process skills (75.4%) as compared to the integrated science process skills (24.6%). Correlation and multiple regression analyses revealed that students’ laboratory performance skills is significantly positively correlated with higher education entrance exam score, availability of laboratory resources and instructors experiences. Instructors’ experience has significant positive regression weights / Life and Consumer Sciences / D. Phil. (Mathematics, Science and Technology Education)

Federal and state agencies in the United States have pressured institutions in higher education to increase the number of graduates in STEM disciplines and supply an educated workforce for the increasing shortages in the STEM economy. Undergraduate research experience is one potential mechanism for supporting retention and student success within STEM disciplines. Most evaluations of the impact of undergraduate research to this point have been qualitative research studies. The purpose of this study was to use a quantitative model to examine domain knowledge, domain interest, and career aspirations in undergraduate biology majors and how participation in research experiences may impact each of these aspects. Path analysis was performed with data collected from an online survey that was administered to six upper level biology courses during one semester. Domain interest and career aspirations was the only significant relation in the path model. Research experiences may indirectly impact career aspirations by increasing domain interest, but additional work is needed to examine this relationship. Stakeholders in undergraduate research at institutions may consider the implications of this study as they develop policies to reduce barriers for student participation in research.

The purpose of this study was to evaluate the undergraduate biology practical instructions and the level of competence of undergraduate biology students in practical laboratory skills in some Ethiopian universities using skill performance rubric and questionnaires. A sample of 208 third year students and 26 instructors and laboratory assistants from three universities were selected as sample of the study. Students reported that more than 84.2% of the laboratory activities are below the average number of laboratory activities recommended by the curriculum with no significant difference between universities. The laboratory skill performance test score was below the midpoint. None of the students could be able to estimate and determine fields of vision of a microscope. There is a significant and a positively linear relationship between the students’ grade point average (GPA) with identification of laboratory equipment, handling of microscope, setting of microscope, estimation of diameter of field of vision and measuring liquid. Laboratory skill performance test score is correlated with higher education entrance exam score but not with students’ high school laboratory back ground. There is no significant difference in instructor’s manipulative skills among universities (p ≥ 0.09) and instructors manipulative skills is neither correlated with qualification nor teaching experience (P≥0.056). The most common method of assessment instructors’ use in the laboratory is laboratory report and identification of specimen examination (46.4%) and written exam and identification of specimen examination (35.7%). The number of courses having laboratory manuals is as low as 14.3%, in the new university. Manipulating materials, measuring and using numbers, and pre lab activity were common activities, and were found in every manual and in every university. Moreover, the result also revealed that the manuals contain high percentage rate of basic science process skills (75.4%) as compared to the integrated science process skills (24.6%). Correlation and multiple regression analyses revealed that students’ laboratory performance skills is significantly positively correlated with higher education entrance exam score, availability of laboratory resources and instructors experiences. Instructors’ experience has significant positive regression weights. / Life and Consumer Sciences / D. Phil. (Mathematics, Science and Technology Education)

<p>In recent years, science has shifted from a focus on reductionist explanations of biological phenomena to a more integrated, systems approach. This shift has made its way into curricular recommendations for undergraduate education. To understand complex biological phenomena, it has been argued that students employ mechanistic reasoning, in which one describes a mechanism by identifying the activities that produce change, the entities which engage in activities, and the starting and ending conditions. Students’ use of mechanistic reasoning requires engaging in the complex task of simultaneously integrating and coordinating multiple elements across space and time. In addition, students must link and organize their scientific ideas and then structure their thoughts into a network of knowledge, as described by the theory of knowledge integration. Previous studies that have explored students’ understanding of scientific concepts using knowledge integration as a lens found that students’ nonmechanistic ideas prevented them from identifying gaps in the connections between their ideas and from forming normative knowledge. Thus, this dissertation investigates the features of undergraduate biology students’ systems thinking using knowledge integration and mechanistic reasoning as conceptual and analytical frameworks. Using a semi-structured interview, we asked students to describe functional definitions of and relationships between three fundamental modules in biology (i.e., gene regulation, cell-cell communication, and the relationship between genotype and phenotype). In the first study, we found that the majority of students did not have normative functional definitions for how and why gene regulation occurs or how phenotype is regulated. When describing the relationships in an open context, most students expressed unidirectional, linear knowledge networks which lacked Mechanistic connections. In our second study, we examined how students described a transition point in biofilm development after being cued to think about the three modules. Though students struggled to transfer over relevant ideas to the biofilm context (such as gene regulation and cell-cell communication processes), we found that explanations were more specified in the nature of connections and content including more Mechanistic descriptions. In the third study, we explored features of biology students’ and instructors’ knowledge networks in an open context and situated to a context of the participants’ choice. Within an open context, most students described multidirectional, non-linear knowledge networks similar to instructors. In the specific context, the majority of students described non-linear knowledge networks, but some students modified their structures to be linear. Although the structures became less complex in the specific context, the nature of connections and content became more specified. Across all studies, we found that context greatly affected students’ systems thinking as revealed by the changing features of the knowledge networks. Specifically, context helped students identify what relationships they deeply understood and could transfer and allowed for the creation of a detailed explanation relevant to the specific biological phenomenon. For students to develop a broad systems perspective of biology, we recommend instructors engage students in the process of knowledge integration. Embed opportunities for students to think about biology concepts in various contexts, particularly where students grapple with nuanced and complex transfer of ideas. These practices will encourage students to form causal, mechanistic linkages between concepts and build an integrated, expert-like understanding of biology.</p>