Before you dive into the details of your project, it is a good idea to consider the big picture. Where do you start? How do you decide what to do and how do you organize your project? What are the steps involved in a biology research project? The information below will provide an overview of what is involved in designing and carrying out an independent research project. Additional detailed information on how to approach each step is provided in Getting Started with Independent Research in Biology.
Identify a question or problem that interests YOU which can be investigated using Tetrahymena.
All good research starts with a good question.
Be creative. Come up with an idea that interests you. Your project can address anything you can observe or measure, and can include questions that ask How, What, When, Who, Which, Why, or Where. For example, if you are interested in the effects of changing weather patterns on aquatic ecology, you might ask, “How do changes in temperature affect the growth rate of Tetrahymena?”
If you don’t have a research project in mind, take a look at the various experimental modules on the ASSET website to get ideas about different biological concepts that are easily examined using Tetrahymena. Then think about what interests YOU and what YOU care about.
Science is a collaborative activity! Discuss your ideas with your teacher and other students.
Framing a good question takes time and effort, but pays off in the long run.
Do some background research – read, evaluate and modify your original ideas as necessary.
Doing background research will make it much easier to frame your question and design your experiment. Use the library and the Internet to find out what is known about your topic, to look for past research on similar subjects, and to learn from the experience of others. Examine the basic concepts related to your question. The ASSET Research Resources Student Handout lists several possible free sources for obtaining articles and other pertinent background materials. Ask your librarian for help in obtaining journal articles and other resources. Electronic databases like Web of Science, Google Scholar, or JSTOR will help you locate sources, and often offer full text electronic documents depending on your library’s institutional subscriptions.
Make a list of key words related to your question. As you work, if you think of additional words that relate to your question, add them to your list.
As you explore your topic, you may want to revise your specific research questions. Using the background information you have gathered and your key words, focus your ideas and refine your question.
Tetrahymena can be used to examine many kinds of biological activities, but no single organism is perfect for looking at all biological phenomena. Make sure to ask a question that can be investigated using Tetrahymena.
Construct a hypothesis
A scientific hypothesis is basically an educated guess that predicts what you think will happen.
A scientific hypothesis should present an idea that can actually be tested. A good scientific hypothesis can be tested by changing something in Tetrahymena’s environment and measuring what happens as a result. Word your hypothesis carefully so that it clearly states what you will change during the experiment (the independent variable) and what you will observe and measure (the dependent variable). Your hypothesis will be supported or disproved by the evidence that you collect by carrying out carefully designed experiments and observations.
Often a scientific hypothesis can be framed as an “If … (this is done) … , then … (this will happen) …” statement. For example, a hypothesis related to the effects of temperature on growth rate might be “If the temperature increases (independent variable), then growth rate (dependent variable) will increase.”
A simple hypothesis is easier to test than a complex hypothesis. A single hypothesis involving many different variables and many different possible outcomes is often very difficult to test. However, multiple simple hypotheses are often useful in designing experiments. For example, if you want to measure the effects of environmental changes on plant growth, don’t test temperature, amount of rainfall, soil type, and rain pH all at the same time. Test each one separately and then you can try testing combinations of the factors.
One hypothesis that must always be considered is the ‘null’ hypothesis, which, simply put, means that what you do in your experiment may not have any effect. It’s important to remember that finding there’s no effect is still a discovery.
Once you have an interesting question and a clear hypothesis, you need to design experiments that will help to answer your question. Planning a well-designed experiment requires thought and careful attention to detail.
You need to plan exactly what you will do and how you will do it. You need to identify which things you will change (independent variables) and which will remain the same (constants) during your experiment. For example, if you want to look at the effect of temperature on Tetrahymena growth rate, you need to consider things like what temperature(s) you want to test, how you will control temperature, how you will measure the effect of the temperature changes, what volume of cells you need, how many samples you need to analyze, and what control conditions you should use.
You also need to consider how many replicates you need in order to get meaningful data. Repeating an experiment helps to verify that your results are real and meaningful, and not just an accident. Depending on the type of experiment, repetition can be done in two ways. You can repeat the experiment at least 3 times, or you can carry out the experimental protocol on at least 3 replicates (for example 3 separate cultures of Tetrahymena) at the same time.
You also need a well-designed control that will act as a standard for comparison to your experimental groups. The control should be exposed to the same conditions as your experimental groups except for the independent variable being tested. It tells you what would have happened to the Tetrahymena if you hadn’t changed your independent variable.
Talk your experimental plan over with your teacher and other students before you begin. In the research laboratory most experiments undergo several modifications in the planning stage before they are actually carried out. These “trial runs” help scientists to figure out the best way to run the final experiment.
Make sure you have everything you will need to complete the experiment before you start. Write a specific check list of materials that you will need and make sure you can get everything. A good materials list is very specific, for example “sterile distilled water” rather than “water”, or “sterile petri plates”” rather than “petri plates.”
Outline your final experimental plan in a step-by-step format. A well-written experimental plan should include enough detailed information that anyone reading it could duplicate your experiment exactly. A good experimental plan also insures that when you do your experiment you don’t omit any critical details.
Carry out your experiment and collect your data
Use a notebook to record ALL of your observations during the experiment. Sometimes you may notice changes you weren’t expecting to see. Write them down. If you have more than one culture growing at a time, make sure you have a way to note which changes you see in which cultures.
Prepare a data table before you start. A prepared data table will allow you to record your results in an organized fashion as you observe them.
Follow your experimental plan carefully. If (as sometimes happens) you need to change your experimental procedure, make sure you write down exactly what changes you made. Write everything you do in your notebook. Never depend solely on your memory.
Collect your data accurately. Be consistent in how you observe and record information. Whenever possible collect numerical data. If you are collecting descriptive data, use the same terms and criteria consistently throughout the experiment. Enter ALL of your data in your notebook, including any details that might affect the results. Consider taking pictures to document your results as your experiment progresses. Pictures will record your observations and may be useful when you prepare your final report.
Analyze your results
Clearly describing and analyzing results are a critical part of science.
Go over your results with a critical eye. Review your procedure and make sure you did not make any mistakes in carrying out your experiment. Make sure your results provide you with enough information to do a meaningful analysis. Determine whether you need any additional data.
If you found that there were problems with your experimental design, think about how you would change your protocol if you were to repeat the experiment.
Present your results in a format that makes the data easily understandable, using data tables, graphs, or simple statistical tests when possible. Tables and graphs can be made by hand, but if you have access to a computer, there are many programs that can be used for making tables, graphs, and even doing simple statistical analyses. Make sure all tables and graphs are clearly labeled and include the units of measurement (degrees C, number of cells, time, etc.). If you present your results in a graph, make sure the independent variable is on the X-axis and the dependent variable is on the Y-axis. If you use a statistical analysis, be sure to describe the type of analysis used and give the results of the statistical test.
Present Your Conclusions
After analyzing your results, you need to reach conclusions about what your research has shown you about your original question. Conclusions may support or contradict your original hypothesis. Sometimes the conclusion will be very straightforward and clear, and other times the conclusions may not supply a complete answer to the question you originally posed. In either case the conclusions should summarize your study and reflect what you have learned by carrying out the experiment.
When putting your conclusions into written form, you should first briefly summarize your project, including a very short description of what question(s) were asked and what you did to answer those question. Make sure to explain the purpose of the study clearly. As part of this summary you should include some key information obtained from your background research (your reading) to help readers understand where your research fits into what is already known and to provide information that may help to explain your results.
A brief summary of your results should be presented in a few sentences, along with your hypothesis and whether or not your results support your hypothesis. Summarize and briefly evaluate your experimental protocol, including its effectiveness in testing your hypothesis. Indicate what your research shows about the relationship between the independent and dependent variables. For example, if you were testing the effect of food supply on Tetrahymena growth, you might say “as the concentration of nutrients increased, the number of Tetrahymena cells increased.”
Discuss how your results support or disagree with your original hypothesis, including any uncertainties that exist in your results or analysis, and how they affect your conclusions. Briefly talk about what new information your research provides, and suggest possibilities for future study. If you found that there were problems with your experimental design, briefly discuss the problem and tell how you would change your protocol if you were to repeat the experiment.
Necessary Parts of a Final Report
Depending on the form you choose for your final report (paper, PowerPoint, video or other), the order may vary, but your report should include the following parts:
- your question and hypothesis (the testable form of your question)
- background information
- description of your procedure
- your data
- conclusions – was your hypothesis supported or not?
- relationship between the variables
- evaluation of your procedure – did it work? what would you change?
- what you discovered that was new
- possibilities for future study
More detailed suggestions for how to organize and present your work in different formats are available.