Experimental Design Concepts

Dr. Quinlan, a biology teacher, explains how to tackle experimental design questions. The video covers key elements of a good experiment, including variables, repetition, and control. An example question from the SQA 2019 National Five Biology paper is analyzed to identify the aim, independent and dependent variables, and how to ensure validity and reliability. The importance of drawing conclusions that match the aim and results is emphasized. The video encourages practice and offers support for students seeking to improve their skills.

What are the three key components of a well-designed experiment?

• Introduction, method, and results

• Observation, theory, and conclusion

• Hypothesis, data collection, and analysis

• Variables, repetition, and controls

How do you identify the aim of an experiment?

• By guessing based on the title

• By reading the first paragraph

• By looking at the conclusion

• By finding a sentence that states the effect of one variable on another

What is the independent variable in an experiment?

• The variable that is ignored

• The variable that is measured

• The variable that is changed by the experimenter

• The variable that is kept constant

Why is it important to keep certain variables constant in an experiment?

• To confuse the participants

• To make the experiment easier to conduct

• To ensure the experiment is valid

• To make the experiment more interesting

Which of the following is NOT a way to maintain constant variables?

• Keeping the temperature the same

• Changing the concentration of solutions

• Using the same species of sample

• Maintaining the same pH level

How can you determine if an experiment is reliable?

• By using different methods each time

• By changing the variables each time

• By conducting the experiment only once

• By repeating the experiment multiple times

What is the purpose of a control in an experiment?

• To provide a comparison for the experimental results

• To ensure all variables are changed

• To increase the complexity of the experiment

• To eliminate the need for repetition

What should a conclusion in an experiment reflect?

• The aim and the results

• The hypothesis only

• The method used

• The introduction

Why is it important for a conclusion to match the aim of the experiment?

• To avoid rewriting the aim

• To confuse the reader

• To make the report longer

• To ensure the experiment is valid

What is a common mistake students make when writing conclusions?

• Ignoring the results

• Matching the conclusion to the aim

• Repeating the experiment

• Using too many variables