GED Science Scientific Practices Scientific Method Hypothesis Experiment Conclusion

What Is This?

The Scientific Method is a systematic process used to develop and test scientific knowledge. It involves making observations, formulating a hypothesis, conducting an experiment, and drawing a conclusion based on the results.

This topic appears in exams to test your understanding of the scientific method and its application in various fields. You can expect to see questions that require you to describe the steps involved in the scientific method, identify the strengths and limitations of a particular experiment, or evaluate the validity of a hypothesis.

Why It Matters

The scientific method is a fundamental concept in science, technology, engineering, and mathematics (STEM) fields. It appears in exams such as the SAT, ACT, AP exams, and graduate school entrance exams. You can expect to see 10-20% of the questions on the scientific method, with a difficulty rating of intermediate to advanced. The examiner is testing your ability to think critically, analyze data, and draw conclusions based on evidence.

Core Concepts

To master the scientific method, you need to understand the following core concepts:

• Hypothesis: A testable explanation for a phenomenon or observation.
• Experiment: A controlled test of a hypothesis, designed to produce reliable and valid results.
• Variable: A factor that can be changed or measured in an experiment.
• Control group: A group in an experiment that does not receive the treatment being tested.
• Independent variable: The variable that is being manipulated or changed in an experiment.
• Dependent variable: The variable that is being measured or observed in an experiment.

Prerequisites

Before tackling the scientific method, you need to understand the following prerequisites:

• Scientific inquiry: The process of asking questions, making observations, and seeking answers.
• Research methods: The techniques used to collect and analyze data.
• Critical thinking: The ability to analyze information, evaluate evidence, and draw conclusions.

If you are missing these prerequisites, you may struggle to understand the scientific method and its application.

The Rule-Book (How It Works)

The scientific method involves the following steps:

1. Make an observation: Identify a phenomenon or observation that requires explanation.
2. Ask a question: Formulate a question based on the observation.
3. Research the topic: Gather information and background knowledge on the topic.
4. Formulate a hypothesis: Develop a testable explanation for the phenomenon or observation.
5. Design an experiment: Plan and design an experiment to test the hypothesis.
6. Conduct the experiment: Carry out the experiment and collect data.
7. Analyze the data: Evaluate the results of the experiment and draw conclusions.
8. Draw a conclusion: Based on the data, determine whether the hypothesis is supported or rejected.

Signal words: Use the following signal words to indicate the different stages of the scientific method:

• If-then: Hypothesis
• Because: Cause-and-effect relationship
• However: Contrasting evidence
• Therefore: Conclusion

Exam / Job / Audit Weighting

Frequency: 20-30% Difficulty Rating: Intermediate to Advanced Question Type or Real-World Task Type: Multiple-choice questions, short-answer questions, and essay questions.

Difficulty Level

Intermediate

Must-Know Rules, Formulas, Standards, or Principles

The following rules, formulas, and principles are essential to the scientific method:

• Null hypothesis: A hypothesis that states there is no effect or no difference.
• Alternative hypothesis: A hypothesis that states there is an effect or a difference.
• P-value: A measure of the probability of observing the results of an experiment, assuming that the null hypothesis is true.

Worked Examples (Step-by-Step)

Here are three solved examples that escalate in difficulty:

Example 1: Easy

A student observes that plants grow faster in soil with added fertilizer. What is the next step in the scientific method?

1. Ask a question: "Does fertilizer affect plant growth?"
2. Research the topic: Gather information on plant growth and fertilizer.
3. Formulate a hypothesis: "Fertilizer increases plant growth."
4. Design an experiment: Plan an experiment to test the hypothesis.

Example 2: Medium

A researcher wants to investigate the effect of exercise on blood pressure. What is the independent variable in this experiment?

• Independent variable: Exercise
• Dependent variable: Blood pressure
• Control group: Participants who do not exercise

Example 3: Hard

A study finds that a new medication reduces blood pressure in patients with hypertension. However, the study also finds that the medication has a side effect of increased heart rate. What is the conclusion of this study?

• Conclusion: The medication reduces blood pressure, but it also increases heart rate.
• Recommendation: Further studies are needed to evaluate the benefits and risks of the medication.

Common Exam Traps & Mistakes

Here are four common mistakes that can cost you marks in exams:

• Mistake 1: Confusing the independent variable with the dependent variable.
• Mistake 2: Failing to control for extraneous variables.
• Mistake 3: Drawing conclusions based on incomplete or biased data.
• Mistake 4: Failing to consider alternative explanations for the results.

Shortcut Strategies & Exam Hacks

Here are some practical techniques to solve questions faster or more accurately under time pressure:

• Memory aid: Use the acronym "OARS" to remember the steps of the scientific method: Observe, Ask, Research, and Solve.
• Elimination strategy: Eliminate options that are clearly incorrect or implausible.
• Pattern recognition: Recognize patterns in the data and use them to draw conclusions.
• Formula shortcut: Use the formula for calculating the p-value to quickly evaluate the results of an experiment.

Question-Type Taxonomy

Here are four distinct question formats that the scientific method appears in:

Practice Set (MCQs)

Here are five multiple-choice questions at mixed difficulty levels:

Question 1: Easy

What is the first step in the scientific method?

A) Ask a question B) Research the topic C) Formulate a hypothesis D) Design an experiment

Correct answer: A) Ask a question Explanation: The first step in the scientific method is to ask a question based on an observation or phenomenon.
Why the distractors are tempting: Options B, C, and D are all important steps in the scientific method, but they are not the first step.

Question 2: Medium

What is the independent variable in an experiment to test the effect of exercise on blood pressure?

A) Exercise B) Blood pressure C) Age D) Sex

Correct answer: A) Exercise Explanation: The independent variable is the variable that is being manipulated or changed in an experiment.
Why the distractors are tempting: Options B, C, and D are all variables that could be measured or observed in an experiment, but they are not the independent variable.

Question 3: Hard

A study finds that a new medication reduces blood pressure in patients with hypertension. However, the study also finds that the medication has a side effect of increased heart rate. What is the conclusion of this study?

A) The medication reduces blood pressure and has no side effects.
B) The medication reduces blood pressure, but it also increases heart rate.
C) The medication has no effect on blood pressure.
D) The medication increases blood pressure.

Correct answer: B) The medication reduces blood pressure, but it also increases heart rate.
Explanation: The conclusion of the study is that the medication has both benefits and risks.
Why the distractors are tempting: Options A, C, and D are all incorrect because they do not accurately reflect the results of the study.

Question 4: Easy

What is the dependent variable in an experiment to test the effect of fertilizer on plant growth?

A) Fertilizer B) Plant growth C) Soil type D) Watering schedule

Correct answer: B) Plant growth Explanation: The dependent variable is the variable that is being measured or observed in an experiment.
Why the distractors are tempting: Options A, C, and D are all variables that could be manipulated or changed in an experiment, but they are not the dependent variable.

Question 5: Medium

A researcher wants to investigate the effect of exercise on blood pressure. What is the control group in this experiment?

A) Participants who exercise regularly B) Participants who do not exercise C) Participants who exercise for 30 minutes D) Participants who exercise for 1 hour

Correct answer: B) Participants who do not exercise Explanation: The control group is the group that does not receive the treatment being tested.
Why the distractors are tempting: Options A, C, and D are all groups that could be included in the experiment, but they are not the control group.

30-Second Cheat Sheet

• Hypothesis: A testable explanation for a phenomenon or observation.
• Experiment: A controlled test of a hypothesis, designed to produce reliable and valid results.
• Independent variable: The variable that is being manipulated or changed in an experiment.
• Dependent variable: The variable that is being measured or observed in an experiment.
• Null hypothesis: A hypothesis that states there is no effect or no difference.
• Alternative hypothesis: A hypothesis that states there is an effect or a difference.
• P-value: A measure of the probability of observing the results of an experiment, assuming that the null hypothesis is true.

Learning Path

To master the scientific method, follow this learning path:

1. Beginner foundation: Understand the basics of scientific inquiry, research methods, and critical thinking.
2. Core rules: Learn the steps of the scientific method and the key concepts, such as hypothesis, experiment, and variable.
3. Practice: Practice applying the scientific method to real-world scenarios and experiments.
4. Timed drills: Practice solving questions and problems under time pressure.
5. Mock tests: Take mock exams to assess your knowledge and identify areas for improvement.

Related Topics

Here are three closely connected topics that appear alongside the scientific method in exams:

• Research methods: The techniques used to collect and analyze data.
• Critical thinking: The ability to analyze information, evaluate evidence, and draw conclusions.
• Statistics: The branch of mathematics that deals with the collection, analysis, and interpretation of data.