NSTA WebNews Digest

Journal of College Science Teaching : Feature

Introduction to Biological Investigations


11/1/2004 - Linda C. Foote and Kathleen A. FitzPatrick

Introduction to Biological Investigations is a course that was developed to introduce the scientific method through practical application. This active, student-centered experience fosters fundamental skills that promote creativity, critical thinking, and scientific communication. The course has been well received by first-year students, and assessment results have been highly positive.

Students workingFor more than a decade there has been an ongoing conversation about the state of science education and the apparent need to set benchmarks to enhance scientific literacy. To demonstrate a level of competency and scientific literacy, students should acquire a certain breadth and depth of knowledge to use when formulating opinions and making personal and social decisions (Rutherford and Ahlgren 1990; Ahern-Rindell 1999). The National Science Education Standards states that scientific, literate individuals “identify scientific issues underlying national and local decisions and express positions that are scientifically and technologically informed” (NRC 1996, 22). By applying those critical thinking skills, graduates become informed members of society (Ahern-Rindell 1999).

The American Association for the Advancement of Science [AAAS (1990)] and the NRC (1999) make the following recommendations for faculty and curricula:

  • Promote independent learning. Engage students in the design and execution of experiments and analysis of results.
  • Enhance the lab experience, emphasizing science as it is practiced rather than as a series of cookbook lab exercises that verify known information.
  • Increase the emphasis on scientific communication skills.

Altering the learning approach to one that is student-driven and not faculty-dispensed assumes new roles for those involved. In this “minds-on approach” (Schamel and Ayers 1992), otherwise known as problem-based or inquiry-based learning, students ask their own questions about biological systems and, within certain guidelines, design their own group experiments. Rather than merely practicing a set of techniques and demonstrating a predicted outcome, participants use the scientific method to carry out self-designed experiments and are more invested and actively engaged.

Earlier studies indicated that students use critical thinking skills and perform better on outcome assessments when they are actively engaged in cooperative group activities and problem-based learning settings (Hufford 1991). Faculty also take on new roles in this experiential en-vironment, acting as facilitators and consultants, and they maintain an environment that supports students’ experimental designs.

Timely Change

For years our curriculum featured traditional exercises with predictable outcomes linked to course-specific subject matter. Some department courses included occasional student-designed experiments, and our second-year human physiology course was based entirely on student-directed investigations (FitzPatrick 2004). Evaluations of the laboratory in our four-credit cell biology course, taken by first-year students in the fall term, indicated that students felt little ownership or sense of engagement with the molecular/cellular level, cookbook-type exercises (studying cellular observation, metabolic reaction rates, and so forth) that introduced techniques discussed in lecture. However, response to the independent physiology labs that stressed scientific process, creativity, and communication was quite positive. Faculty also questioned the usefulness of the former lab, because students arrived in subsequent courses lacking fundamental skills in communication, experimental design, creativity, and independent thinking.

Guided by recent evidence of a strong correlation between high achievement and student-centered investigations (Russell and French 2001; Di Pasquale, Mason, and Kolkhorst 2003), we adopted radical changes in our approach by developing a formative course for all students in their first semester of our major programs. In addition, the college’s current strategic plan values and encourages experiential learning, group work, and investigative activities.

Students working on computersTo better prepare students for their academic and professional futures, and specifically to enhance their scientific literacy, we eliminated the lab associated with cell biology, reducing it to a three-credit lecture. At the same time, we developed a required three-credit seminar/lab experience called Introduction to Biological Investigations, to be taken as an added biology course in the first term. Our goals in designing the lab were to introduce the scientific method through practical application and to foster students’ skills in the following:

  • developing specific experimental questions and hypotheses;
  • designing and executing experiments;
  • collecting, managing, analyzing, and presenting data; and
  • formally communicating scientific results, both in writing and orally.

Student survey results after two years of assessment were both informative and highly positive (Foote, FitzPatrick, and Lyon 2002). We also conducted a three-year assessment of the course.

Assessment Method

Context of the study. Our institution is a small, private, comprehensive college with 2100 students. In the first three years the course was offered, 190 students (62% female and 38% male) completed it. The majority (73%) was first-year students, with a smaller number (17 and 7%, respectively) of second- and third-year students transferring into the college and/or the major. The average entering SAT scores of biology department students during this period were 523 ± 68 for verbal and 542 ± 73 for math. Because the majority was first-year students, they had had no college-level science or math; admissions requirements for these majors include four years of high school math and three of science. During their first term, students were also taking cell biology lecture and general chemistry lecture/lab. Students did not generally take math until the second term. The five or six sections offered each term were taught by three or four faculty members as part of their normal 12-hour teaching load.

Students attended a weekly 3-hour faculty-facilitated seminar/laboratory session in which they examined examples of the hierarchal organization of biology in four experimental systems, presented in multiweek modules. The experiments included studies of lectin-mediated cell-cell interactions, physiological responses of neurogenic and myogenic hearts, human cardiovascular fitness, and ecological responses to environmental pollutants (Table 1).

Table 1. Introduction to biological investigations calendar.

Week 1
Introduction to cardiovascular fitness
Experimental design and execution
Week 2
Introduction to information literacy and library resources
Introduction to statistics and computer graphing
Data management and analysis

Week 3
Physiological responses of myogenic and neurogenic hearts
Experimental design
Submit formal CV fitness lab report
Week 4
Experiment execution
Data management and analysis
Week 5
Research team presentation
Peer evaluation

Week 6
Cell-to-cell interactions mediated by lectins
Experimental design
Submit formal physiological responses lab report
Week 7
Experiment execution
Data management and analysis
Week 8
Research team presentation
Peer evaluation

Week 9
Ecological responses to pollutants
Experimental design
Submit formal lectin lab report
Week 10
Experiment execution
Data management and analysis
Week 11
Research team presentation
Peer evaluation
Week 12
Submit formal pollution lab report

Each multiweek module began with a presentation of the system or model and the techniques or methods used to test hypotheses related to it. For example, the dissection of a crayfish and the monitoring of its heart rate were demonstrated. Student research teams then developed a specific testable hypothesis, designed controlled experiments, determined what data would be collected, and predicted the ways in which the data would be managed and presented. (An experimental design sheet is available as Web Figure 1 at the end of this article.)

The instructor reviewed the experimental design and noted the necessary equipment and reagents. During the following week, students carried out the experiments and collected, organized, and analyzed data. Prior to the third week, research teams met outside the lab to prepare posters, overheads, or PowerPoint slides. In the third week, teams presented their findings to the class. The group discussed the results, and the presentation content and delivery were graded in a peer-reviewed process using a checklist assessment tool (available as Web Figure 2 at the end of this article).

To further enhance students’ scientific communication skills, professional librarians gave students formal instruction in information and literature searches; this was done early in the semester. Through a process of written drafts of the traditional sections of formal scientific reports passed between student and instructor, and supported by the efforts of an upper-class writing fellow, students generated formal laboratory reports for each experimental module (Table 1). In addition, early in the term, students received formal instruction in the use of the KaleidaGraph computer graphing package, and all subsequent presentations and reports were required to contain only computer-generated graphs.

Data collection and analysis. Evaluation surveys were administered during the last class of the term in all course sections. The narrative surveys (available as Web Figure 3 at the end of this article) were passed out at the beginning of the class, and students were allowed 10 to 15 minutes to write their anonymous responses. All students present completed the surveys, which we then collected and analyzed.

At the end of each course in 2000, 2001, and 2002, narrative surveys were administered. For each question, we pooled all sections and performed a content analysis to identify the major themes in the responses. In Figures 1 through 4, results indicate the percent of total responses for the six topics.

A single reader recorded all responses and then identified recurring general themes or comment types for each question. The number of responses reporting each comment type for each question was tallied and reported as a percent of the total respondents for each year. Figures 1 through 4 present the six highest-ranking comment themes for each question in each year, generally those reported by 10% or more of the students. Additional comments made by less than 10% of students were recorded but are not presented here.

Student writing portfolios showed the development of individual writing skills, and we archived selected portfolios for a longitudinal study of skills development over the students’ four-year program. This analysis is ongoing.

Study Results

Survey results for three years, completed by 83% of students taking the course, indicate that students identified the ability to design their own experiments and the ability to write effective scientific reports as the most positive aspects of the course. Additionally, students mentioned scientific thinking skills, experience with oral communication, hands-on learning, and group work (Figure 1).

Figure 1

In specific reference to the written and oral reports, students most appreciated the opportunity to give oral presentations, share results with and learn from other students, learn writing skills, give and receive written and oral feedback, and revise multiple editions of their reports (Figure 2). Students commented:

  • The most positive aspect was creating our own experiments to test the topic. It allowed us to be creative and even heightened our understanding of the topic.
  • Through developing our own experiments, I was really able to use problem-solving skills as well as work in a group.
  • Developing my own experiments has helped because it gets me more involved in the process and more interested rather than being given an experiment to do.
  • I was very surprised when I found out we’d be allowed such independence. This is excellent! It’s just what we need and provides a great gateway to more advanced experimental research.

Figure 2

The features students said they most appreciated about the formal written reports and the oral presentations included the following:

  • I liked being able to hand in the draft of the lab report and receive feedback. Through this method, I really learned how to organize and write a lab report.
  • The oral presentations helped me to feel confident of my knowledge of the topic and gave me new ideas to write about in the final lab report.
  • By writing the report and “teaching” to the class I gained a better understanding of the material.
  • It helps fine-tune the people and communication skills that we will use in everyday life when working. The skills developed will last a lifetime.

When asked to identify the least positive aspects of the course, students commonly indicated that they found no negatives. The magnitude of the workload required, group dynamics, and oral reports, were problems for some students. They said:

  • The workload seemed intense at first, although I shortly learned time management skills.
  • I did not necessarily enjoy the oral presentation aspect of the course but I know it is important.

Figure 3

Although a few students suggested some possible changes (Figures 3 and 4), students’ most common response was that no changes were required. Students said:

  • I would not change anything about the format or assignments. I think this class does an excellent job achieving the goals.
  • I wouldn’t change it. Of all my classes, this is the most interesting.

Figure 4

No examinations were given; grades were determined from oral and written reports. From the examination of portfolios, within each year, instructors have seen consistent improvement in students’ written work and in presentations from the first to the last of the term.

Study Conclusions

We have implemented and assessed this experience for the last three years. The data strongly suggest that the program’s benefits outweigh its limitations. The positive features reported here are consistent with those reported by others implementing investigative laboratories. Grant and Vatnick (1998) also report that students reacted very positively to designing their own experiments and to oral presentations to classmates.

McGraw (1999) noted that 93% of students rated an investigative ecology laboratory as good or excellent. In a molecular biology laboratory, Ahern-Rindell (1999) reported that students identified similar features of creativity, enhanced understanding, critical thinking, group skills, and increased interest as positive aspects of the experience. Similar points were identified in an investigative exercise physiology lab (DiPasquale, Mason, and Kolkhurst 2003). In a research study, Russell and French (2001) noted a more positive relationship between achievement and hands-on laboratories in the inquiry-based model than in cookbook labs. They also found that female students participated more equally, compared to males, in both manipulation and discussion, in the inquiry-based model.

To summarize, the experiments instill excitement. The students are curious about the outcome of their projects. They feel a sense of ownership and are proud of their accomplishments. Students appreciate abandoning highly predictable exercises.
Individual students are challenged to develop and refine their literature research and writing skills. The weekly writing assignments, with multiple opportunities for revision and redrafting, fulfill the collegewide objective of writing across the curriculum while developing precision and clarity in scientific thinking and expression.

The research teams foster active and collaborative learning while students design, execute, analyze, and present experiments. Concepts are reinforced as teams develop oral communication skills by sharing, debating, and critiquing their peers’ designs, data, and analyses. The course develops foundation skills for upper-level classes, which can build on this experience, adding higher-level skills of collaborative writing, primary literature use, and statistics. Students who have taken this foundation course arrive in upper-level laboratories with better-developed writing, communication, and experimental design skills, as compared to the previous standard cell biology lab.

In an analysis of the first report grades in the spring term first-year core course Introduction to Genetics (BI 112), students not previously enrolled in BI 115 (genetics classes of 1998 and 1999) were compared with those of students who had completed BI 115 (classes of 2000, 2001, and 2002). The average grades for students in the latter group were 83.8 ± 12.0 (n = 32); these were significantly higher than those of the former group, which were 58.5 ± 19.4 (n = 19, P < 0.001, two-tailed t test).
The laboratory accompanying our second-year physiology course is organized similarly to BI 115. The average grades on the first experimental design and report in physiology for students who had not had BI 115 (physiology classes of 1998, 1999, and 2000) were compared with those of students who had had BI 115 in their first year (classes of 2001, 2002, and 2003). The average grades for students in the latter group were 88.2 ± 4.6 (n = 45); these were significantly higher than those for the former group, which were 82.8 ± 6.4 (n = 57, P < 0.001, two-tailed t test). As a result of the basic scientific communication skills developed in BI 115, more time in upper-level courses can now be spent polishing and adding new design, analysis, and presentation skills.

Additionally, the course is more intellectually challenging for faculty because it increases their interaction with students. Working through designs on various biology topics, many of which are outside the primary research areas of individual faculty members, is more stimulating than simply supervising technique as students follow directions in the standard lab. In this setting, the course introduces students to faculty as collaborators; as they see faculty working through the processes of science with them, students are exposed to faculty research interests, thus potentially involving them in faculty research projects earlier in their academic careers. Grant and Vatnick (1998) and Ahern-Rindell (1999) both point out advantages of this approach.

Limitations of this approach are few. Faculty must be mindful that students arrive on campus with diverse backgrounds and levels of preparation; therefore, some students require more direction and encouragement. As the assessment results indicate, group dynamics are sometimes problematic and faculty members generally have not been trained in facilitation of group work. Peer leadership and the academic support provided by the upper-class writing fellow can help to level the playing field.

This approach to learning can be a time-sink. The experimental design work, literature searches, statistical analysis and graphing, preparation for presentations, and formal writing are all conducted outside the designated seminar/laboratory time. Students must quickly understand the commitment and develop the necessary time-management skills. Coordinating and outfitting supplies and reagents for student-designed experiments requires many 11th-hour purchases and preparations.

We have the advantage of a half-time lab technician and half-time lab manager to support this effort. Having flexible and cooperative staff is helpful, but for those without such services, careful choice of less time- and equipment-intensive experimental systems could reduce the preparation and support demands on instructors. We have found that, with a judicious choice of experimental systems, expenses for course materials actually decreased in comparison with the traditional cell biology lab. Finally, time spent in discussion with groups as they plan and refine their experiments, along with grading of experimental design sheets, drafts, and final reports are time consuming for the instructor. It is our experience that small classes of 12 to 16 students guarantee the opportunity to provide the essential encouragement and feedback.

Study Summary

In a one-semester seminar/laboratory experience, students are introduced to, adopt, and practice the skills of research scientists. They enthusiastically and collaboratively execute the scientific method, which, in this context, represents structured curiosity—a process for asking and provisionally answering questions about mechanisms and relationships that explain observations about the natural world. From observations of a given biological phenomenon, in various contexts both within and outside the laboratory, students are guided to develop testable questions/hypotheses that might explain the relationships or mechanisms behind the observations.

Students design and execute experiments to test explanations; they gather and analyze data to support or refute the explanations and compare these with the results of others. Based on these collective results and insights, further observations and continued curiosity, the hypothesis might be abandoned or revised to begin the entire process again. Any explanations supported by the current experiments are understood to be provisional, always subject to refinement or rejection as further observations and creative insights arise.

In this experience geared toward first-year students, we aim to develop students’ basic understanding and competence in the fundamental procedural steps of the method. In time, students may become more creative and competent in their critical thinking skills and their ability to communicate. Finally, they appreciate the foundations set here and understand how this experience becomes the first of many opportunities to use these life-long skills. Student participants reinforce these scientific literacy and communication skills when enrolled in their second-semester course, Introduction to Genetics. With this foundation, students in upper-level courses can cultivate greater creativity and the ability to question the philosophy and application of the method itself.

Linda C. Foote (e-mail: Linda.Foote@Merrimack.edu) and Kathleen A. FitzPatrick (e-mail: Kathleen.FitzPatrick@Merrimack.edu) are associate professors in the Department of Biology and Allied Health, Box N8, Merrimack College, 315 Turnpike Street, N. Andover, MA 01845.

Web Figure 1. Experimental design worksheet.

Adapted from www.bates.edu/~ganderso/biology/resources/expdesign.html.

1. What is the question/problem you want to investigate? What is your testable hypothesis? What is/are your expected outcome(s) if your hypothesis is supported?

2. What data do you need to obtain in order to test your hypothesis? Indicate units of the actual measurements and how the data would be summarized and/or normalized (i.e., mean ± SD, %, mm/sec, etc.).

3. What is/are the treatment(s)? Be specific with quantitative parameters (concentrations, stimuli, etc.). Give some thought here as to what kind of statistical analysis you'll perform. It is prudent to make sure you can analyze the data later using routine statistics.)

4. What is/are your control(s) for the variable(s) being tested? What will each control tell you?

5. What is one replicate in your experiment? How many replicates (e.g., measurements, observations, trials) in each treatment level and control will there be? Consider how long it takes to get one observation and how much time you have.

6. Outline the step-by-step procedure you'll use to obtain a single measurement or observation, and be sure to specify all the quantitative parameters (how much, how long, when, what dose, etc.) and the equipment used for each step. This must be precise and clear enough that anyone can do it with a consistent level of accuracy and complete enough for anyone to replicate your experiment with comparable equipment.

7. How will your data be summarized, analyzed, and presented? Show relevant calculations (e.g., normalization of data, etc.) and indicate the statistical tests you'll use. For graphic presentation, indicate the type of graph and the variables to be plotted. For KGraph users, consider how the data sheet will be set up to facilitate analysis of the data.

8. State any assumptions you are making in doing this experiment and justify them, (i.e., explain your rationale for making them). How will know if your assumptions are not met?

9. List all materials you will need that have not been provided already.


Web Figure 2. Presentation evaluation

Group names_______________________________________
Topic_____________________________________________
Please rate each of the following on a scale of 1 to 4, where 4 = excellent, 3 = above average, 2 = average, and 1 = below average:

Did the speakers provide enough background information to allow you to understand the nature and importance of the experiment?

Was the hypothesis or question being asked clear, and did it make a prediction about the expected outcome?

Were the methods described clearly?

Did the speakers address how the data were collected and analyzed? What stats were performed?

Was the presentation of results clear?

Were the graphs and tables explained (including statistics)?

Did the data support the hypothesis?

Did the presenters describe the possible problems or sources of error in the data?

Did the presenters summarize the major finding of the experiment at the conclusion of the talk?

Was the presentation organized and clear?

Were the use of the blackboard and visual aids effective?

Did the presenters rely too heavily on notes?

Was eye contact effective?

Was the pace of the presentation appropriate?

Any further comments?


Web Figure 3. Student assessment

This evaluation is intended to help faculty continue to develop and improve BI 115. Your help is greatly appreciated and will benefit future students and the faculty who teach BI 115.

The Introduction to Biological Investigations course was designed to meet the following specific goals:

1. Introduce students to the scientific method and, through practical application, foster skills in:

  • Developing experimental questions and specific hypotheses
  • Experimental design
  • Data collection
  • Data analysis
  • Written and oral communication

2. Develop both written and oral communication skills.

  • Based on format examples from Pechenik and the Laboratory Manual Guide to Authors and through a process of drafts passed between the student and the instructor, foster the development of a full laboratory report.
  • Through a process of example and peer review, develop skills in delivering clear and concise oral presentations.

Please answer the following questions.

With regard to your practical experience using the scientific method and developing your own experiments, what has been the most positive aspect? Provide an example.

In this experience, what has been the least positive? Explain.

What do you appreciate most about the formal written reports and the oral presentations?

How would you change the format or assignments (this includes additions as well as deletions) to better achieve the specific goals of this course?

Acknowledgments

We thank the students and faculty of the Merrimack College Biology and Allied Health Department for their efforts and support in the development and revision of this curriculum.

References

Ahern-Rindell, A.J. 1999. Applying inquiry-based and cooperative group learning strategies to promote critical thinking. Journal of College Science Teaching 28(3):203–207.
AAAS. 1990. The Liberal Art of Science: Agenda for Action. Washington, D.C.: AAAS.
AAAS. 1993. Benchmarks For Science Literacy: Project 2061. Washington, D.C.: AAAS.
DiPasquale, D.M., C.L. Mason, and F.W. Kolkhorst. 2003. Exercise in inquiry. Journal of College Science Teaching 32(6):388–393.
FitzPatrick, K.A. 2004. An investigative laboratory course in human physiology using computer technology and collaborative writing. Advances in Physiology Education 28(3):112–119.
Foote, L., K.A. FitzPatrick, and J. Lyon. 2002. Introduction to Biological Investigations: A First Year Experience in Experimental Design and Scientific Communication. 9th National Conference of the Council on Undergraduate Research, Connecticut College, New London, Conn. June 19–22, 2002.
Grant, B.W., and I. Vatnick. 1998. A multi-week inquiry for an undergraduate introductory biology laboratory. Journal of College Science Teaching 28(2):109–112.
Hufford, T.L. 1991. Increasing academic performances in an introductory biology course. Bioscience 41(2):107–108.
McGraw, J.B. 1999. The total science experience laboratory for sophomore biology majors. Journal of College Science Teaching 28(5):325–330.
NRC. 1996. National Science Education Standards. Washington, D.C.: National Academy Press.
National Research Council. 1999. Transforming Undergraduate Education in Science, Math, Engineering and Technology. Executive Summary. Washington, D.C.: National Academy Press.
Russell, C.P., and D.P. French. 2001. Factors affecting participation in traditional and inquiry-based laboratories. Journal of College Science Teaching 31(4):225–229.
Rutherford, F.J., and A. Ahlgren. 1990. Science for All Americans. New York: Oxford University Press.
Schamel, D., and M.P. Ayers. 1992. The minds-on approach: Student creativity and personal involvement in the undergraduate science laboratory. Journal of College Science Teaching 21(4):226–229.
Siebert, E.D., and W.J. McIntosh, eds. 2001. College Pathways to the Science Education Standards. Arlington, Va.: NSTA Press.

Sponsored by:

All