7.1.2 Experimental Design

• What is the first step in the scientific method?

  Observation
• An experiment is designed to test a hypothesis


  True
• The final step in the scientific method is to draw a conclusion
• What is the key difference between controlled and uncontrolled experiments regarding the key variable?

  Manipulated vs. not manipulated
• What is the definition of an independent variable?

  The variable manipulated by researcher
• Match the variable with its role in an experiment testing fertilizer's effect on plant growth:

  Amount of fertilizer ↔️ Independent variable

  Plant height ↔️ Dependent variable
• The second step in the scientific method involves proposing a testable explanation
• What type of data is collected in the fourth step of the scientific method?

  Quantitative or qualitative
• Controlling variables in an experiment is crucial for drawing reliable conclusions.

  True
• What is absent in an uncontrolled experiment?

  Control group
• The independent variable is the one that the researcher manipulates.


  True
• The independent variable causes changes in the dependent variable
• When testing the effect of fertilizer on plant growth, factors like temperature and water supply must be controlled variables
• Match the group type with its characteristic:

  Experimental Group ↔️ Independent variable is manipulated

  Control Group ↔️ Independent variable is not manipulated
• Precise measurements are essential for ensuring high accuracy in data collection.

  True
• Blinding in data collection prevents unconscious bias
• Controlled experiments are crucial for establishing cause-and-effect relationships.


  True
• In an experiment testing the effect of fertilizer on plant growth, the amount of fertilizer is the independent variable.
• If you are testing the effect of fertilizer on plant growth, the amount of fertilizer is the independent variable.
• How does the dependent variable respond to changes in the independent variable?

  It is measured or observed
• What is the purpose of control variables in experimental design?

  Ensure changes in the dependent variable are solely due to the independent variable
• Control variables ensure the reliability of experimental conclusions.


  True
• Steps to design a controlled experiment

  1️⃣ Formulate a hypothesis

  2️⃣ Identify variables

  3️⃣ Establish a control group

  4️⃣ Set control variables

  5️⃣ Create a procedure

  6️⃣ Collect data

  7️⃣ Analyze data
• In a controlled experiment, the independent variable is manipulated in the experimental group.
• What is the primary goal of quantitative data in a data collection plan?

  Provide objective and reliable data
• A testable explanation for an observation is called a hypothesis
• What is the purpose of data analysis in the scientific method?

  Determine if data supports hypothesis
• Controlled experiments are essential for establishing cause-and-effect relationships


  True
• A control group is present in a controlled experiment but absent in an uncontrolled experiment.
• The dependent variable responds to changes in the independent variable


  True
• What is the first step in the scientific method according to the material?

  Observation
• Designing and conducting a controlled test is the third step in the scientific method.


  True
• Interpreting the data to determine if it supports or refutes the hypothesis is called analysis
• Match the type of experiment with its characteristic:

  Controlled Experiment ↔️ Key variable is manipulated

  Uncontrolled Experiment ↔️ Key variable is not manipulated
• In an uncontrolled experiment, the relationship between cause and effect is unclear
• What is the definition of the dependent variable?

  Variable measured or observed
• Control variables are factors kept constant to isolate the effect of the independent variable.


  True
• What is the role of control variables in an experiment?

  Eliminate confounding variables
• Steps to design a controlled experiment

  1️⃣ Formulate a hypothesis

  2️⃣ Identify variables

  3️⃣ Establish a control group

  4️⃣ Set control variables

  5️⃣ Write a detailed procedure

  6️⃣ Collect data

  7️⃣ Analyze data
• A well-designed data collection plan includes collecting quantitative data rather than qualitative observations.