Part 1 In teams of two, use bullet points to write a controlled experiment for the Daphnia experiment below

Sure! Here's a structured outline for a controlled experiment using Daphnia, presented in bullet points: --- ### **Controlled Experiment Outline: Effect of [Independent Variable] on Daphnia** #### **1. Objective** - **Determine** how varying levels of [independent variable] affect [dependent variable] in Daphnia. #### **2. Hypothesis** - *If* [independent variable] is increased/decreased, *then* [dependent variable] will increase/decrease accordingly. #### **3. Materials** - Live Daphnia specimens - [Independent Variable] source (e.g., different light intensities, varying concentrations of a substance) - Petri dishes or small aquariums - Water of consistent quality (e.g., same temperature, pH) - Microscope for observation - Timer or stopwatch - Measuring instruments (e.g., light meter, pipettes) - Control setup materials (same as experimental but without the independent variable) #### **4. Variables** - **Independent Variable:** [Specify what you will change, e.g., light intensity, concentration of a pollutant] - **Dependent Variable:** [Specify what you will measure, e.g., heart rate of Daphnia, mortality rate] - **Control Variables:** - Water temperature - pH level - Volume of water in each container - Quantity of Daphnia in each group - Duration of exposure - Light exposure (except for the independent variable being tested) #### **5. Experimental Groups** - **Experimental Group(s):** - Exposed to varying levels of [independent variable] - **Control Group:** - Exposed to standard conditions without the [independent variable] #### **6. Procedure** 1. **Preparation:** - Set up multiple containers with equal amounts of water. - Ensure all containers are at the same temperature and pH. 2. **Grouping:** - Divide Daphnia evenly into each container, ensuring equal numbers across all groups. 3. **Exposure:** - Apply different levels of [independent variable] to each experimental group. - Keep the control group without the [independent variable]. 4. **Observation:** - After a set period (e.g., 24 hours), observe and record the [dependent variable] using a microscope. - Repeat observations at consistent intervals if necessary. 5. **Replication:** - Conduct multiple trials to ensure reliability of results. 6. **Data Collection:** - Record all observations systematically for analysis. #### **7. Data Analysis** - Compare the [dependent variable] across different levels of the [independent variable]. - Use statistical methods to determine the significance of the results. #### **8. Conclusion** - Determine whether the results support the hypothesis. - Discuss possible reasons for the outcomes and any anomalies observed. #### **9. Controls & Considerations** - Ensure that only the [independent variable] differs between experimental and control groups. - Maintain consistent environmental conditions across all groups. - Handle Daphnia gently to prevent stress that could affect the results. --- **Example Scenario:** *If testing the effect of light intensity on the heart rate of Daphnia:* - **Independent Variable:** Light intensity (e.g., low, medium, high) - **Dependent Variable:** Heart rate of Daphnia (beats per minute) - **Control Variables:** Water temperature, pH, number of Daphnia, duration of light exposure --- This structured approach ensures that the experiment is well-controlled, allowing for reliable and valid results. Good luck with your Daphnia experiment!