from Inquiry, Volume 6, Number 1, Spring 2001
© Copyright 2001 Virginia Community College System
Return to Volume 6, Number 1
Carmichael outlines a new technique for helping students understand the scientific method.
What Is a BioProject?
BioProjects are simple, quantitative biological investigations that students conduct outside of class, using readily obtainable measurement tools and easily developed skills.† Students choose the questions they investigate (with guidance from the instructor), make oral presentations describing their projects, and submit written assignments that collectively comprise a standard-format scientific research paper.
Even instructors with research backgrounds often have difficulty describing "the scientific method."† Concepts such as hypotheses, variables, sampling and drawing reasonable conclusions from data remain vague abstractions to students unless concrete examples are used.† BioProjects give students the opportunity to be scientists, and as they investigate questions related to their own interests, they replace abstractions with the specifics of their projects.† BioProjects enhance students' oral and written presentation skills, attention to detail, and appreciation for the challenges of answering even simple scientific questions with confidence.† Moreover, students develop the ability to evaluate critically the voluminous scientific information they encounter beyond the classroom.† After BioProjects progressively introduces the mechanics of scientific investigation, students can answer the question "What is the scientific method?" by asserting "It is what we have done."
It is vital that students understand the type of questions that science can and cannot answer.† Quantitative investigations must address measurable changes or differences, such as:
††††††††††††††††††††††† * Does birdseed consumption change over time?
††††††††††† or†††††††† * Is there a difference in lung capacity of males and females?
(See other suitable BioProject questions below.)
More complex "How?" or "Why?"
science questions are answered by the progressive accumulation of answers to
such simple questions.† BioProjects
should be limited in their complexity;† however, in two-semester General
Biology courses students have the opportunity to perform consecutive, related
investigations whose results cumulatively approach complete answers.
A hypothesis is an informed guess about the answer
to an investigative question.† No
hypothesis can be said to be wrong if it is supported by information from a
student's previous reading, experience or observation.† A hypothesis should do more, however, than
simply answer the question in a "yes" or "no" fashion:† it should describe an expected relationship
between the variables to be measured in an investigation.† For example, a reasonable hypothesis for the
question "Is there a difference in the lung capacity of males and
females?" might be:† "Males
have larger lung capacities than females," and reasonable support might be
based on the larger average body size of males.†
Providing support for a hypothesis is a good exercise in referencing
existing scientific information in written assignments.
Variables are the parameters that must be measured, counted or observed in order to answer an investigative question, and every quantitative investigation involves at least two variables.† (First-semester BioProject investigations should be limited to two variables.)† For the question regarding lung capacities of males and females, the two variables are lung capacity and sex of the subjects.† In most investigations, one variable clearly depends upon or is influenced by the other;† in this case, lung capacity depends upon the sex of the subject.† This relationship defines which is the dependent variable† and which is the independent variable, important distinctions in designing investigations and for displaying results in a graph.† (Dependent variables are always displayed on the y-axis of a graph.)
Sometimes a dependent variable depends upon more than one independent variable.† (Lung capacity also depends upon athletic activity and smoking history.)† Since most investigations seek to determine the effect of only one independent variable upon the dependent variable, these other factors are confounding variables, and must be controlled within the investigative design.† (Make sure all male and female subjects have similar exercise and smoking backgrounds.)† Confounding variables often confuse the cause and effect relationship, and students must learn to be careful when drawing causative conclusions from their results since confounding variables can rarely be completely controlled.
The concept of continuous
(e.g., time, distance) and discontinuous variables (e.g., sex, location)
should also be addressed since it impacts choice of graphing style.† (The effects of continuous independent
variables are best displayed in line graphs; the effects of discontinuous
independent variables should be displayed in bar graphs.)
Sampling and Statistics
No matter how simple the questions
they pose, few scientific investigations can produce definitive answers because
sample sizes are limited.† In
BioProjects, sample sizes are restricted by practical considerations, and it
soon becomes obvious to students that larger sample sizes produce more
believable results.† When changes or
differences are measured in BioProjects, students are often the first to doubt
the reality of those differences.† This
skepticism provides concrete opportunities to discuss important principles of
statistical analysis:† what statistical
tests can show and how results can be made more statistically reliable.† Even students with limited mathematics skills
can understand these concepts; some students may choose to conduct
"simple" statistical tests of their data (like the Student's
t-Test).† Most students eventually
realize that hypotheses can rarely be proven to be true; instead, data
can merely support or not support a given hypothesis.
The most valuable instruction in designing and executing scientific investigations can take place in regularly scheduled laboratory periods.† If every meeting becomes an investigative session, the concepts described above quickly become familiar to students.† In a typical session, the instructor might:
1)†††††††† Pose a simple investigative question about changes or differences. (Is there a difference in the lung capacity of male and female students?)
2)†††††††† Ask students to identify the two variables to be determined.
3)†††††††† Ask students to identify which is the dependent and which is the independent variable.
4)†††††††† Ask students to pose a reasonable hypothesis and support it.† (Accept any well-supported hypothesis.)
5)†††††††† Ask students how to measure, count or observe each of the two variables.
6)†††††††† Ask students what they think a practical sample size would be.
7)†††††††† Ask students if there are any confounding variables.
8)†††††††† Ask students how the investigation can be designed to minimize the impact of those confounding variables on the results.
9)†††††††† Ask students to measure, count or observe the two variables.† (Measure lung capacities with spirometers and record the sex of each student.)
10)†††††† Ask students to display all their data in a table on the blackboard. (Stress proper, user-friendly table format.)
11)†††††† Ask students to calculate means of the dependent variable values at each independent variable category or value.
12)†††††† Ask students to create a graph on the board showing these means.† (Stress simple, user-friendly graph format.)
13)†††††† Ask students to draw a reasonable conclusion from the data summarized in the graph.
14)†††††† Ask students how the investigation could be improved if repeated.
15)†††††† Ask students to pose another related question that will more completely identify the cause of the changes or differences measured.† (Make one of the confounding variables the next independent variable.)
16)†††††† Request that students submit a written description of methods, their table, graph, or a complete investigative report.
The BioProject Guide and BioProject Assignments
In the author's classes, a comprehensive BioProject Guide is distributed to students.† It defines the BioProject as a whole, the instructor's expectations and assignment deadlines, all investigative principles, and proper table and graph formats.† It also provides numerous sample BioProject questions, checklists of expected assignment features, and samples of well-written reports.
The first written BioProject assignment can be a short, written Introduction which poses the question the student has chosen, a hypothesis, reasonable support for the hypothesis, identification of the variables, and a short description of the methods selected to measure them.† This assignment (due three to four weeks into the semester) should be preceded by an individual meeting with the instructor to approve the question's suitability and guide the studentsí choice of methods.
The second written assignment (due the sixth week of the semester) may be a detailed description of the proposed methods sufficiently precise to allow someone else to also conduct the investigation.† It should include the techniques to be used to measure, count or observe each variable, the sample size, location and proposed dates of the study, and a description of all materials and measurement tools to be used, including where they were obtained.† The overall design should mitigate the impact of any significant confounding variables.† This assignment may be followed by a brief oral presentation to the class describing the contents of the first two written assignments.
The third written assignment is due near the end of the semester after the investigation is complete (thirteenth† or fourteenth week).† It should contain the Introduction and Methods (re-written and corrected to contain any changes encountered during execution of the project), a Results section containing at least one table and one graph, and a Conclusion and References section.† The Conclusion should clearly indicate if the original hypothesis was supported or not, possible explanations of unexpected results, suggestions for improvement of repeat investigations, and another related question whose answer could advance understanding of the phenomenon investigated.† Submission of this assignment may be followed by an oral presentation of the entire BioProject using overhead transparencies to display results in a table and graph.
Posters containing all the information in the final
report may be required or offered as extra credit assignments.† When posters from previous semesters are
displayed in classrooms or hallways, they provide new students with excellent
models of BioProject characteristics and the instructor's expectations.
Caveats and Difficulties
The author's experience has shown that students need many examples to firmly grasp the concepts associated with BioProject investigations. †Performing as many investigations as possible in the laboratory is the best way to accomplish this understanding.† Despite many students' professed familiarity with reading tables and graphs, constructing them is an entirely different matter; again, numerous hands-on examples are valuable.
A ten-minute individual meeting with each student to help him or her select a BioProject question is essential to ensure it fits the available tools and materials, and each student's skills, lifestyle, and interests.† It is also advisable to suggest table and graph formats at that meeting.† At the end of their meeting, students should understand how every measurement will be made and how results might be presented in tables and graphs.
Writing skills vary widely among General Biology students, so it is important to provide sample written reports and accept simple, formulaic formats for assignments.† In the author's classes, pre-submission of written assignments is encouraged; these are corrected and returned ungraded, so students may re-submit in perfected form by the deadline.† Rarely are written assignments lengthy, so if pre-submissions are accommodated, high expectations can be maintained.
Some science instructors at other VCCS colleges have indicated that this cycle of individual meetings, pre-submissions and widely varied research topics is not feasible in larger classes.† The author has found that 70 to 80 different BioProjects each semester are a strenuous but manageable workload in conjunction with other laboratory and lecture teaching and additional, unrelated college responsibilities.
After students have mastered BioProjects in two
semesters of General Biology, they comprise an excellent resource of trained
labor for instructors' own research projects, or further independent student
investigations.† Instructors may offer
VCCS credit for these efforts by registering students for Bio 199 or 299
Sample BioProject Questions
Listed below are some questions that students have successfully investigated in recent semesters at Virginia Highlands Community College.† For each question, consider:
∑ What are the dependent and independent variables?
∑ How could they be measured?† What equipment and materials are needed?
∑ What confounding variables might be encountered?
∑ How could the impact of confounding variables be minimized?
∑ What is a good hypothesis?
1)†††††††† Does an insect trap catch different numbers of insects in a pasture and on a forest floor?
2)†††††††† Are there more deer on the north or south side of Laurel Bed Lake?
3)†††††††† Does the number of dead opossums on the highways change with the seasons?
4)†††††††† Do red maple trees grow at different rates at different elevations?
5)†††††††† Are the rainbow trout bigger in Whitetop Laurel Creek or Beaverdam Creek?
6)†††††††† Does fishing success (e.g. number of strikes per 100 casts) change in different phases of the moon?
7)†††††††† Do different kinds of music affect the heart rates of humans? dogs? horses?
8)†††††††† Does goldfish activity level change during the day?
9)†††††††† How rapidly do puppies gain weight?† ostriches?† iguanas?† human babies?
10)†††††† Does the number of births/emergency room visits/arrests change with the phase of the moon?
11)†††††† Does music affect the growth of plants?
12)†††††† Does birdseed consumption change with time?† with temperature?
13)†††††† Is plant richness/diversity different in grazed and ungrazed pasture?
14)†††††† Do plants grow differently if watered with water of different pH's?
15)†††††† Does electrical current affect the growth of plants?
16)†††††† Does the number of Canada geese on the ponds in Saltville change with the time of day?
17)†††††† Does the size of lichens vary with the age of the tombstone they are on?
18)†††††† Is there a difference in the abundance of lichens on north- and south-facing surfaces of trees/tombstones?
19)†††††† Does sleep deprivation affect mental ability?† depth perception?† resting heart rate?† 20) Does body temperature change during the day?
21)†††††† Does metronome clicking affect the resting heart rate of humans?† dogs?
22)†††††† Does catnip increase heart rate of cats?† dogs?† humans?
23)†††††† Is the abundance/richness/diversity of aquatic insects in Whitetop Laurel Creek different above and below the town of Damascus?
24)†††††† Does smoking affect sense of smell?† taste?
25)†††††† Does bee activity change at the hive during the day?
26)†††††† Do different red maple trees have different amounts of insect damage on their leaves?
27)†††††† Do different varieties of tobacco produce different weights of tobacco per plant?
28)†††††† Do resting heart rates differ between smokers and non-smokers?† exercisers and non-exercisers?
29)†††††† Does caffeine affect heart rate?† Does decaffeinated coffee affect heart rate?
30)†††††† Does body temperature change during the menstrual cycle?
31)†††††† Does the abundance of plankton in South Holston Lake change with the seasons?
32)†††††† Is there a difference in the rate of fish gill movements in water of different temperatures?
33)†††††† Does water temperature affect fishing success?†
34)†††††† Does water quality affect lettuce seed germination?† (lettuce seed bioassay)
35)†††††† Does body temperature change during exercise?
36)†††††† Is resting heart rate different in dogs of different weights?
37)†††††† Is there a difference in the germination rate of bean seeds from different suppliers?
38)†††††† Is there a difference in the turbidity of the Middle and South Forks of the Holston ††††††††
39)†††††† Is there a difference in the fertility of soils collected from beneath different tree †† species?
40)†††††† Does viewing different colors affect heart rate?
Doug Carmichael worked as a farmer, veterinary assistant, wastewater plant operator, zookeeper and wildlife researcher and then earned a Ph.D. in Cell and Molecular Biology from the University of Tennessee in 1993. He now teaches General Biology, Microbiology, Introductory Biochemistry, Aquatic Biology and Backpacking at Virginia Highlands Community College.