FACILITATING INQUIRY IN COLLEGE-LEVEL BIOLOGY COURSES_____________
MARY V. BALL
Biology Department, Carson-Newman College, Jefferson City, TN 37760
STEVE KARR
Biology Department, Carson-Newman College, Jefferson City, TN 37760
A major component of inquiry is the analysis of appropriate data, but how can we expect students to be enthusiastic about analyzing and interpreting data when both they and we know that much student-generated data is of poor quality? We have identified a variety of potentially effective strategies for improving data quality and promoting a focus of data analysis and interpretation, including use of data collection protocols that are simpler and more reliable, creating in-house databases that allow sharing of data across lab sections and from semester to semester, and using online databases as a source of data. Modifications in course structure and coordination have also been necessitated, including a reduction of the number of topics covered in lab at the introductory level, data collection outside regularly scheduled lab times, provision for time for oral presentation of inquiry proposals and outcomes during lab sessions, and application of the same research protocols in successive courses.
Introduction
In our experience, a significant barrier to effective inquiry in college-level biology courses has been the tendency for student-generated data to be of poor quality. Contributing factors include complex or unreliable laboratory protocols, time and equipment limitations, and the tendency for lab manuals to incorporate a different protocol in every exercise. For several semesters, we have explored a variety of potential solutions.
Issues Related to the “Typical” Lab Manual, “Prep Time”, and Equipment/Supplies
OUR EXPERIENCE TO DATE
In our experience, the “typical” General Biology lab manual still uses the traditional “cook book” approach, in which students are given step-by-step instructions for obtaining preordained outcomes. Students typically work in teams to perform un-replicated experiments, with no data pooling. The focus during the lab session is on filling in a data chart, with little attention to the underlying rationale for the lab protocol. Drawing of conclusions, if required at all, generally involves merely providing written answers to questions at the end of the exercise, questions that are often unclear.
For small colleges, such as ours, issues of “prep time” and equipment/supplies become significant. The “prep time” required to get ready for conducting the lab often is excessive and it is frequently impossible to provide each lab team with a complete set of equipment and supplies.
By carefully reviewing potential manuals, we have been able to identify some that at least suggest “questions for further inquiry” and that use relatively simple protocols that require less “prep time”.
ONGOING CHALLENGES
The potential cost-saving to students of adopting a textbook and lab manual from the same publisher, so that they can be sold “bundled”, has conflicted with our desire to select a manual based on our goal of promoting inquiry. We have considered the option of creating a “customized” manual, but have not had the manpower to tackle this task.
Selection of Experimental Protocols
OUR EXPERIENCE TO DATE
We have observed that, in general, “low-tech” protocols are to be preferred at the freshman level because students are more likely to be able to understand the rationale for the steps in the procedure, thereby making fewer mistakes. In reviewing potential protocols, we look for protocols that are easy to “prep”, yield reliable results, can be used to answer a variety of inquiry questions, and can be applied in two or more successive courses.
An example of such a protocol is the use of clear fingernail polish to create stomata impressions that can be examined with a microscope. The density, size, and arrangement of stomata can be tabulated to explore diversity between and within species and to correlate stomata density to various environmental factors. The technique is appropriate for General Biology, Botany, and Ecology courses.
ONGOING CHALLENGES
Protocols that appear to be relatively straightforward often contain unidentified potential pitfalls. There is a need for “Prep Manuals” that are much more thorough, with attention to pointing out potential pitfalls and to suggesting alternatives that would allow conducting the lab with limited equipment.
As an example of potential pitfalls, consider the protocol for making a root tip smear. With experience, one can get a “good” smear virtually every time. However, in a lab of novices, getting only one or two good smears is not unusual. We have identified several potential errors novices are likely to make – overheating the tissue, accidentally “wicking up” the tissue along with the excess solution, having the tissue dry out during staining because the table is not level and the stain shifts, not applying sufficient pressure during the “squash” procedure, and, finally, inability to locate and properly focus the cells with the microscope.
A good example of alternatives would be for an exercise involving catechol oxidase, an enzyme responsible for the “enzymatic browning” reaction in fresh fruits. Since the production of dark-colored product can be assayed either qualitatively (by color) or quantitatively (with spectrophotometers), providing both protocols would give instructors greater flexibility.
Creating In-house Databases
OUR EXPERIENCE TO DATE
Sharing of data across lab sections and across semesters allows students to pool similar data and to benefit from what previous inquiry teams have accomplished. Pooling of data has helped us to avoid a problem we experienced in the past, that of students struggling to interpret the results of un-replicated experiments. Sharing of results from previous semesters has allowed inquiry teams to formulate inquiry questions based on prior observations, reducing the need for us to “suggest” potential inquiry questions.
ONGOING CHALLENGES
There is a need for coordinating the process of data storage and retrieval.
Online Databases as a Means for Obtaining and/or Sharing of Data
OUR EXPERIENCE TO DATE
DNA and protein sequence data can be accessed online and manipulated with a variety of online tools. We have incorporated an introduction to bioinformatics in General Biology with a lab exercise in which students search for and align preproinsulin sequences from different species, comparing the sequence similarities for the signal sequence, the C peptide, and the A and B insulin chains. We have observed that, even though we have a computer lab with enough computers for students to work alone, having students work in pairs results in far fewer “calls for assistance”.
ONGOING CHALLENGES
A number of national online projects involving data sharing are now in existence. Although many of these target K-12, the potential use of the data at the college level would be worth exploring. The creation of data-sharing projects for the college level should also be explored.
Laboratory Schedule Modifications
OUR EXPERIENCE TO DATE
By reducing the number of topics covered in lab during a semester, we have been able to allow students to learn a data-collection protocol one week and apply it the next week to answer a question of their own. In the early stages of teaching students the process of inquiry, we have found it desirable to also schedule a proposal-sharing session, in which inquiry groups critique one another’s plans. (In the past, proposals were turned in for prior approval, but we have found that reading and approving written plans in advance often fails to prevent major errors in design, such as confounding of variables, errors that are much easier to identify during an oral proposal presentation.)
We have had to reconsider the notion that labs meet once a week, with no data collection outside of the scheduled lab time. For many valuable protocols, it is unrealistic to limit data collection to once a week. Students are given advance notice of which weeks to expect to have to coordinate with members of their inquiry team in collection of data outside lab time.
An Inquiry Conference lab session, in which inquiry groups present their results and conclusions, provides motivation for careful analysis of data and for self-critique. Individually written research reports are also required, following the format introduced “in pieces” earlier in the semester.
ONGOING CHALLENGES
Although our students are required to take Statistics and to interpret statistical results from primary literature in our Directed Readings and Senior Seminar courses, we have not yet resolved the issue of effectively having them use statistics to analyze data.
Coordination Among Successive Courses
OUR EXPERIENCE TO DATE
Some protocols, such as growing Wisconsin Fast Plants, can be applied in more than one successive course, such as General Biology, Botany, Genetics, and Ecology. This allows students in successive courses to investigate more topics during a single semester and to explore topics in greater depth.
Because fewer topics are covered in the General Biology labs, we have had to collaborate in identifying topics that can either be omitted entirely or deferred to later courses. For example, as a result of our decision to focus on human biology in the General Biology course and defer the in-depth coverage of the Animal Kingdom until the Zoology course, we no longer dissect fetal pigs in the General biology course.
ONGOING CHALLENGES
Even though we have a relatively small department, it is difficult of those faculty that do not teach the General Biology course to become familiar with the protocols introduced in that course. There is a need for other faculty to experience the protocols and to plan for their potential incorporation in advanced courses.
Acknowledgements
We would like to acknowledge our colleagues in the Biology Department, Patsy Boyce, Susan Karr, Bob Trentham, Mike Page, and Steve Wright, all of whom have collaborated with us in our ongoing efforts in promote inquiry in our biology courses at Carson-Newman College.
Bios
Mary Ball is a Professor of Biology at Carson-Newman College. She is Past President of the Tennessee Environmental Education Association.
Steve Karr is Associate Professor and Chairman of the Biology Department at Carson-Newman College. He and Mary have conducted professional development workshops for K-8 teachers on Inquiry-Based Science Teaching for the last 6 years.
References
We are developing an annotated list of links to publications, websites, and lab exercises that could be useful to persons attempting to promote inquiry in college (and high school) biology courses. The Inquiry Webliographer (http://webliographer.com/Inquiry/) is a project in progress. Contributions can be made to the site by clicking on How To Participate and then following the given instructions.
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