Name ______________________________________________________ Period __________ LAB: Planarian Regeneration Background Information: If you’ve ever had an injury, a repair process started in your body. The injury may have left a scar that might still be visible. That scar tissue was different from the original tissue. In some organisms, the process of regeneration produces new tissues that have the same structure and function of the original tissue. How might an understanding of how these animals regenerate tissues help humans? As a group, you will observe planarians' physical and behavioral characteristics and then develop a hypothesis related to their regenerative abilities. LAB SETUP: MATERIALS: ❏ planarians ❏ 2-3 Petri dishes ❏ Spring water ❏ Plastic transfer pipette ❏ Planarian food (hard boiled egg yolk) ❏ Metric ruler ❏ 1 piece of light color paper ❏ 1 piece of dark color paper ❏ Dissecting microscope or hand lens ❏ cavity slide ❏ coverslip ❏ labeling tape and permanent marker ❏ Scalpel ❏ forceps ❏ phone flashlight Which materials are you familiar with or used before? Which materials are you not familiar with and have not used before? What are potential safety hazards in this lab? What steps are you taking to prevent these safety hazards? PROCESS AND PROCEDURE: PART 1: It will be important to learn more about the characteristics and behavior of planarians. Read the “Need To Know: Planarians on p. 392 of your textbook ❏ Transfer COLD spring water into a Petri dish so that it is halfway full. Use a pipette to transfer one planarian into the Petri dish. ❏ Wait for the planaria to stretch out. Use a metric ruler to measure the length and width of the organism. ❏ Describe how the planarian moves. ❏ Use a dissecting microscope or hand lens to more closely observe the body plan. ❏ On the next page, accurately sketch the planarian. At minimum, label the following characteristics: anterior end (head), posterior end (tail), eye spots, and mouth. ❏ In the“Need To Know: Planarians on p. 392, you read that planarians can detect light intensity. Use the dark and/or light paper and/or your phone flashlight to determine if the planarian can detect light. Describe what you did and the planarian’s resulting behavior. (see next page) ❏ You read that planarians have a gastrovascular cavity and that the mouth is located on the ventral side. Add a small piece of the food (liver, egg yolk, daphnia) to the Petri dish. Describe how the planarian responds to food. Planaria Characteristics (Anterior and posterior ends, eye spots, mouth, gastrovascular cavity) Labeled Sketches must be: Accurate Big Enough Colorful Detailed Explanation PART II: Experimental Design ❏ What does it mean to regenerate? ❏What questions do you have about planarian regeneration? ❏How might our group investigate planarian regeneration? Behavior (Response to cold water, light, and food) ❏ With your group, develop one testable question to investigate. Refer to the Planarian Resource Sheet to help you plan and carry out your investigation. (See last page of this booklet) Have your teacher approve your question. Write it here: QUESTION: If we cut our planarian in ______ different places will it regenerate into ______ separate organisms? ❏ Write the hypothesis related to your testable question. HYPOTHESIS: I think it will take _________ days to fully regenerate because _____________________________________________________________________________ ______________________________________________________________________________ ❏. What are the variables of the experiment: Controlling Variables: (What remains the same throughout the experiment?) Manipulated Variables: (What are the things that you’ll be changing on purpose?) Responding Variables: (Because you manipulate something in the experiment, what’s the effect, or response?) ❏ Write the step-by-step plan of your controlled experiment; explaining what you’ll do in order (1st, 2nd, 3rd, etc.) Anyone should be able to follow your plan and achieve the same results. Again, Refer to the Planarian Resource Sheet to help you plan and carry out your investigation. (See last page of this booklet) 1. First we will… 2. After that we will . . . 3. Next thing will be . . . 4. Rinse Repeat, etc. . . . 5. Lastly . . . . LAB DATA: Observations of Planarian Regeneration Characteristics and Behaviors. Your group will record observations every 3–4 days for the next 2 weeks. You will also need to provide the planarians with food and fresh spring water. WORDS AND PICTURES Remember ABCDE Day # & Date Day ___ __/__/__ Day ___ __/__/__ Day ___ __/__/__ Day ___ __/__/__ Planarian (Control) Planarian 1________________ (Experimental) Planarian 2 __________________ (Experimental) Day ___ __/__/__ Day ___ __/__/__ Day ___ __/__/__ Day ___ __/__/__ CONCLUSION: ❏ What story did your data tell? What patterns and/or changes did you notice? ❏ Did the data support your hypothesis: Yes/No? Why/Why not? ❏ What did you learn from doing this experiment? (Use the back of this page if you need additional space)
