The Cell Theory: A Historical Perspective A WebQuest for High School Biology Designed by Jennifer O'Connor oconnorj@fc.manatee.k12.fl.us Introduction | Task | Process | Evaluation | Conclusion | Credits Introduction If someone were to tell you that people once believed that maggots came from rotting meat or that rats came from damp roofs, you would quickly write the person off as being very weird. However, this IS what many people thought until about 250 years ago. These beliefs were based upon an idea called "spontaneous generation." Why did people accept this absurd idea? How was this idea finally put to rest? It's up to you to find out! During this webquest, you will learn about the scientists who helped to pave the way to the development of the Cell Theory and to the rejection of spontaneous generation. Back to top The Task You will use internet resources to create a timeline that begins with the invention of the compound microscope to the experiment conducted by Louis Pasteur that finally dispelled the outdated idea of spontaneous generation. After completing your timeline, you should summarize the three parts of the cell theory in your own words. Your timeline is to be created using Inspiration software. Back to top The Process PART A - RESEARCH The list of scientists that you should highlight in your quest are as follows: 1) Zacharias Jansen 2) Anton van Leeuwenhoek 3) Robert Hooke 4) Matthias Schleiden 5) Theodor Schwann 6) Rudolf Virchow 7) Louis Pasteur You may use the resource under "Credits & References" to get you started but you are encouraged to search other sites as well. Keep a list of sources that you visit. Cite these sources on your timeline in a small bubble or box that is off to the side. As you conduct research with regards to these scientists, ask yourself the following questions: * How did this scientist contribute to the cell theory? (Keep in mind that many of these guys did all sorts of cool things. Make sure the information that you provide here is related to the cell theory.) * When did this scientist make his contribution to the cell theory? * How did this scientist's invention, idea, or experiment help lead to the rejection of spontaneous generation? PART B - YOUR TIMELINE Now that you've gathered all of the information, it's time to put it into a timeline format. 1) Open your Inspiration software. 2) Begin by creating your main idea "bubble." Your main idea can also serve as the title of your timeline. Make sure you include your name in the main idea bubble! 3) Go ahead and save your document now. Save it as your last name and timeline. Example: smithtimeline 3) Now you may create the actual timeline. How you decide to present the information is up to you however the information should be clear and concise. Look at other timelines on the internet, in your textbook, or examples provided by your teacher. 4) Once you have added all of the main events, end your timeline by summarizing the cell theory in your own words. 5) Look over your timeline again. Correct any grammatical errors and add any last minute touches. Save your document and turn it in to your teacher as instructed. Back to top Evaluation Please read over the rubric below. You will be graded individually for this assignment. Beginning 1 Developing 2 Accomplished 3 Exemplary 4 Score Accuracy Information shows no research on the part of the student and/or many items are incomplete and/or information was copied and pasted from sources. Information contains multiple inaccuracies and/or is missing a substantial amount of information and/or is very wordy. Information contains minor inaccuracies and/or is missing some information, and/or is somewhat wordy or unclear. Information is accurate and complete. It is written in a clear and concise fashion. Creativity Creativity is completely lacking. No color or images used. Some effort to be creative. Color and images may not be relevant to assignment. Assignment is colorful and includes images yet it is lacking innovation. Assignment is original, colorful, and includes images. Student went above and beyond the parameters of the assignment. Grammar There is no evidence of appropriate grammar in the assignment. Multiple grammatical errors are present but text still shows some effort on the part of the student. Few grammatical errors are detected. No grammatical errors are detected. Use of technology Student did not use technology to complete this assignment even though technology was available and/or student used research time to view inappropriate websites. Student attempted to use technology but needs more practice. Student conducted research in an efficient manner and/or used the technology appropriately. Student has an excellent grasp on the use of Inspiration software and successfully researched the information in an efficient and independent fashion. Back to top Conclusion Now that you have completed your research and timeline, answer the questions below in complete sentences. (Your teacher will indicate whether to complete these questions on paper or using your laptop.) 1. How did Janssen's, Hooke's, and Leewenhoek's work contribute to the work of the scientists that came after them? 2. How would our lives be different if we had never realized the existance of microorganisms? Provide at least one example to support your answer. 3. Describe the concept of spontaneous generation. Why do you think it took such a long time for people to accept that this idea was incorrect? 4. How do you think the cell theory impacted later scientific discoveries? Explain your answer. 5. The microscope and numerous experiments lead to the rejection of spontaneous generation. This idea had been accepted by most people, including scientists, for over 200 years. How does this demonstrate the true nature of science? 6. Review Pasteur's experiment. Relate his experiment to the scientific method. a. What was Pasteur's question? b. State a reasonable hypothesis based upon this question. c. What was the independent variable in Pasteur's experiment? What was the dependent variable? d. What did Pasteur conclude from his experiment? 7. Examine your timeline. How long did it take to develop the cell theory? What does this imply about the formulation of a theory? 8. Why do we still consider the cell theory a theory? Explain your answer. Back to top Credits & References Image of Leeuwenhoek courtesy of: www.unitedstreaming.com. Leeuwenhoek Biography Back to top