Nature of Science - Vocabulary Flashcards
Concepts/Skills
- Be able to make predictions from analyzing data from a chart, table or graph.
- Be able to identify and interpret the results/conclusion of an experiment from a chart, table or graph.
- Be able to identify the independent variables, dependent variables and the experimental group from a chart, table or graph.
- Be able to explain how bias can negatively affect an experiment or scientific investigation.
- Be able to organize data from an experiment into a chart, table, or graph, and interpret it.
- Analyze data with respect to hypothesis and draw an appropriate conclusion.
- Be able to select the most appropriate hypothesis and identify variables when given the description of a scientific investigation.
- Be able to explain the difference between a theory vs law and theory vs hypothesis.
- Describe the components to the scientific method.
- Be able to explain how scientists communicate the results of a scientific experiment/investigation to ensure accuracy.
Learning Objectives – Key Points
1) In your own words explain what a theory and a law are.
- A theory is a well-supported explanation of natural phenomena that can explain a wide range of observations and make testable predictions.
- A law describes a consistent, universal relationship or rule in nature that is supported by extensive empirical data and observations.
2) How is scientific theory and scientific law similar?
- Both are based on evidence gathered from observations and experiments.
- Both are testable and subject to revision with new evidence.
- Both represent robust understanding of natural phenomena, but neither is merely a guess.
3) Explain why a theory can never become a law and vice versa?
- A theory explains why phenomena occur; a law describes what happens under certain conditions. Theories explain mechanisms behind observations; laws describe consistent relationships. They occupy different roles and cannot simply transform into one another.
4) Give an example of hypothesis in the correct format.
- General format: If the independent variable changes, then the dependent variable will change, because [rationale].
- Example:
\text{Hypothesis: If sunlight exposure (IV) increases, then plant height (DV) will increase, because photosynthesis rate increases with more light.}
5) In your own words, explain how you can identify the independent and dependent variable in a written experiment.
- Independent variable (IV): the variable you deliberately change or manipulate.
- Dependent variable (DV): the outcome you measure.
- The description will indicate what is deliberately altered (IV) and what is measured as the result (DV).
6) Explain how you can identify the independent and dependent variable in a graph.
- IV is typically plotted on the x-axis (horizontal axis).
- DV is plotted on the y-axis (vertical axis).
- Look for labels like "IV" and "DV" or descriptions showing cause (x) and effect (y).
7) What is the difference between observation and inference?
- Observation: information gathered using senses or instruments (data or facts).
- Inference: a conclusion or interpretation drawn from observations.
8) Explain how bias can affect an investigation or an experiment.
- Bias can skew data collection, measurement, sampling, or interpretation, leading to inaccurate conclusions or overgeneralization. It can affect objectivity and reproducibility.
9) Why is a peer review an important component to the scientific method?
- Peer review provides validation, replication checks, and critique from other experts, increasing reliability and credibility of results.
10) Why are repeated trials necessary in a scientific experiment/investigation?
- Repetition reduces random error, increases precision, and helps establish reliability and reproducibility of results.
11) What variables should be held constant during an investigation?
- All variables other than the independent variable that could influence the outcome should be kept the same (constants/controlled variables).
12) List the general steps in designing and conducting an experiment and briefly explain what the scientist does in each one.
- Ask a question: identify what you want to investigate.
- Form a hypothesis: propose a testable explanation.
- Plan/Design the experiment: decide independent/dependent variables, controls, sample size, and methods.
- Collect data: perform trials and gather measurements.
- Analyze data: compare results to the hypothesis and assess trends.
- Draw conclusions: state whether results support or refute the hypothesis.
- Communicate results: share methods, data, and interpretation to ensure accuracy and allow replication.
13) Why is it important in a controlled experiment that the scientist isolates and tests a single variable?
- Testing one variable at a time isolates cause-and-effect relationships and reduces confounding factors, increasing the validity of conclusions.
14) Give an example of a scientific investigation or experiment, with appropriate constants and variables (Independent Variable and Dependent Variables).
- Example: Investigating how light exposure affects seed germination rate.
- IV: Light exposure level (e.g., dark, dim, bright)
- DV: Germination rate (percentage of seeds germinated)
- Constants: Seed type, soil, water amount, temperature, pot size, duration of exposure
15) What is the difference between control group and experimental group.
- Experimental group: receives the independent variable manipulation.
- Control group: does not receive the manipulation or receives a standard/default condition for comparison.
Variables and Experimental Design
- Independent Variable (IV): the variable deliberately changed by the experimenter.
- Dependent Variable (DV): the variable measured and observed.
- Constants/Controlled Variables: factors kept the same across all groups to ensure a fair test.
- Experimental Group: exposed to the IV level(s).
- Control Group: baseline condition for comparison.
- Inference vs Observation:
- Observation: data collected through senses or instruments.
- Inference: interpretation or explanation of observations.
- DRY MIX (visuals) – how it relates to graph interpretation:
- DRY MIX stands for the typical roles of independent/dependent variables on a graph and related graph components.
Scientific Method and Communication
- Components of the scientific method:
- Question
- Hypothesis
- Experimental design
- Data collection/analysis
- Conclusion
- Communication/peer review for accuracy and reproducibility
- How scientists communicate results to ensure accuracy:
- Clear description of methods and data
- Transparent reporting of uncertainties
- Use of charts/tables/graphs for data presentation
- Reproducibility through detailed protocols
- Peer review for validation
Data Representation and Graphs
- Be able to organize data from an experiment into a chart, table, or graph, and interpret it.
- Be able to identify and interpret results/conclusions from charts/tables/graphs.
- Parts of a graph (visual vocabulary): axis labels, scale, data points, trend line, legend, units, title.
- Independent and Dependent Variables on a graph (DRY MIX): identify IV on x-axis, DV on y-axis, interpret relationship.
Theory, Law, Hypothesis – Key Distinctions
- Theory: well-supported, broad explanation of phenomena; explains how and why.
- Law: concise statement describing consistent relationships in nature; often mathematical.
- Hypothesis: testable educated guess about the outcome of an experiment, stated in If-Then form.
Example Formats and Practice
- Example of hypothesis in correct format (above in Learning Objectives).
- Practice: identify IV, DV, controls from written descriptions or graphs; discuss potential biases; outline a short experimental design.
Summary of Important Terms (Vocabulary)
- Science
- Biology
- Controlled experiment
- Theory
- Law
- Hypothesis
- Bias
- Independent Variable
- Dependent Variable
- Constant/Controlled Variables
- Experimental Group
- Control Group
- Inference
- Observation
Visual Vocabulary (Key Concepts)
- Parts of a graph
- Independent and Dependent Variables on a graph (DRY MIX)
- Theory
- Law
- Hypothesis
- Bias
- Independent Variable
- Dependent Variable
- Constant/Controlled Variables
- Experimental Group
- Control Group
- Inference
- Observation