Overview
This lecture introduces the process of designing a scientific investigation, focusing on its key components, formulating aims, and drawing conclusions based on experimental findings.
Key Components of a Scientific Investigation
- The main parts of a scientific investigation are the aim/problem, materials and equipment, method/procedures, results/data, and conclusion.
- The aim (or problem) is a clear, specific, answerable, and measurable question guiding the experiment.
- Materials and equipment should be adequate, safe, available, compatible with the experiment, and accurate for reliable measurements.
- The method is a detailed, clear, and sequential plan that is repeatable by others.
- Results include all data collected, presented as observations, measurements, tables, charts, or graphs.
- Conclusions interpret results, answering the aim based solely on collected data.
Examples of Scientific Investigation Aims
- Investigate the effects of temperature on the rate of photosynthesis in green algae.
- Investigate the effect of different soil pH levels on the growth rate of tomato plants.
Hypothesis and Variables
- A hypothesis is an educated guess about the experiment’s outcome, based on observations and prior knowledge.
- The independent variable is what you deliberately change (e.g., sunlight amount).
- The dependent variable is what you measure in response (e.g., plant growth).
- Controlled variables are kept constant to ensure a fair test (e.g., water amount, pot size).
Key Terms & Definitions
- Scientific Investigation — a process to answer specific questions through controlled experiments.
- Aim/Problem — the specific question or objective of the experiment.
- Materials and Equipment — the tools and supplies required for the experiment.
- Method/Procedure — step-by-step instructions for performing the experiment.
- Results/Data — observations and measurements collected during the investigation.
- Conclusion — interpretation of results, stating whether they support or reject the hypothesis.
- Hypothesis — a testable prediction based on prior knowledge.
- Independent Variable — the factor intentionally changed in the experiment.
- Dependent Variable — the factor measured or observed.
- Controlled Variable — conditions kept constant to ensure a valid test.
Action Items / Next Steps
- Complete the vocabulary match-type activity to reinforce key terms and definitions.
- Prepare to design your own scientific investigation, following the steps outlined.