Study sheet: Scientific Methodology and Experimental Design

📋 Course Outline

1. Science and the Study of Life
2. Observation and Scientific Questions
3. Inference and Testable Hypothesis
4. Variables, Controls, and Experiment Design

📖 1. Science and the Study of Life

🔑 Key Concepts & Definitions

• Biology : the study of life

★ Must-know

• Scientific methodology involves using an organized approach to investigate natural occurrences.

Further detail

• Classroom exploration includes:
  • oral interaction
  • small-group work
  • sharing with other groups

📖 2. Observation and Scientific Questions

★ Must-know

• An observation can lead researchers to ask why a natural occurrence is happening.

• The research began when someone noticed that grass was growing taller in one location than in another.

Further detail

• In the scenario, the difference in grass height between locations was the observation that initiated the research.

💡 Memory Hook

Observation of unequal grass growth → question about its cause

📖 3. Inference and Testable Hypothesis

★ Must-know

• A hypothesis about grass growth must predict a measurable or testable factor that could explain the natural occurrence.

📌 An inference is a general statement based on an observation and is generally not testable, whereas a hypothesis is a testable prediction that identifies a factor or variable that can be measured or tested.

Further detail

• In the grass scenario, the inference was that something was making the grass grow more in location B.

💡 Memory Hook

Inference explains generally; hypothesis predicts testably

📖 4. Variables, Controls, and Experiment Design

★ Must-know

📌 The control group provides a comparison that shows whether the results are related to the nitrogen treatment or whether the grass would have grown the same without added nitrogen.

• In the grass experiment, nitrogen was the independent variable and grass growth was the dependent variable.

📌 The independent variable is the factor controlled by the experimenter, whereas the dependent variable is the factor measured during the experiment.

📌 The control group receives no nitrogen, whereas the experimental group receives the nitrogen treatment.

Further detail

• Designing an experiment requires applying the discussed steps, then sharing the proposed experiment with other students.

💡 Memory Hook

Independent variable is controlled; dependent variable is measured

📊 Synthesis Tables

Inference and Hypothesis

Notion	Basis	Testability
Inference	Observation	Generally not testable
Hypothesis	Prediction identifying a measurable or testable factor	Testable