Scientific Practices
What is the first step scientists take when beginning an investigation that starts from an observation?
Ask a testable question / define a problem
What is an independent (test) variable? Give the quick memory phrase from class.
True or false: Scientific knowledge never changes. Explain your answer in one sentence.
False — science updates as new evidence appears.
What is a prototype?
Prototype = early model used to test and improve a design.
Define bias in scientific investigations in one short sentence.
Bias = an unfair influence that affects decisions or results.
Name two types of data and give one example of each.
Quantitative (numbers — e.g., mass, height) and qualitative (descriptions — e.g., color, texture).
What is a dependent (outcome) variable? Provide a short example (plant experiment).
Dependent = what I measure; Example: plant height (cm) depends on hours of light.
What is the difference between a scientific law and a scientific theory (one-sentence each)?
Law = describes a pattern (often mathematical); Theory = explains why with strong supporting evidence.
Name two criteria and two constraints that might apply when designing a water bottle for hikers.
Criteria: must hold 1 L, be leak-proof; Constraints: material limited to cardboard, time limit 30 min (examples).
Give two examples of how scientific discoveries have impacted daily life (two different fields).
Health (vaccines), Technology (phones/internet) — other valid examples include agriculture, transportation.
List three core actions scientists use to build knowledge (from the lessons).
Define a problem, plan & carry out investigations, collect/organize/interpret data (others acceptable if match lesson wording)
Define a control (or control group) and explain its purpose in a fair test.
Control group provides baseline for comparison so you can see effect of independent variable.
Give two recurring themes in science and a short example for each (one sentence each)
Examples: Patterns (seasonal temp changes), Cause & Effect (light increase → plant growth increase).
What is cost-benefit analysis in engineering? Give a short classroom example.
Cost-benefit analysis = compare advantages vs. costs/trade-offs; e.g., stronger material costs more money but lasts longer.
What questions should you ask to check the credibility of a source? List three.
Who authored it? Are sources cited? Is data/evidence provided? Is it consistent with other reliable sources?
What must a strong conclusion include when scientists defend it?
Cite specific data, explain how controls/multiple trials support findings, discuss errors and improvements.
Explain the difference between a constant (control variable) and a variable that is tested.
Constants are kept the same (e.g., soil, pot size); tested variable is purposely changed (e.g., fertilizer type).
Why are repeated trials important in investigations? Include the technical term used for multiple trials by the same team.
Repetition (multiple trials by same team) reduces random error and increases confidence; replication = other scientists repeat the work.
Describe three steps engineers take after testing a prototype (use the design-process vocabulary).
Test & evaluate (collect data), redesign/improve based on evidence, communicate results (report/presentation).
Explain what a trade-off is and give one example related to building a new bridge.
Describe how you would use reference materials before running an experiment — give two specific purposes.
Examples: build background knowledge, refine hypothesis, choose methods/materials, learn correct measurements or safety procedures.
Identify the independent, dependent, and at least two control variables for an experiment testing fertilizer type on plant growth.
Independent = fertilizer type; Dependent = plant growth (height or mass); Controls = soil type, pot size, water amount, light (as appropriate).
Explain how models, laws, and theories relate to new evidence — what happens if new data disagree with a model or theory?
Models/theories are revised or improved when new evidence disagrees; sometimes hypotheses are rejected or modified.
Explain how optimization works in engineering using a short example (one or two sentences).
Optimization = use test results to improve design; e.g., change shape of mask filter to increase airflow while keeping protection.
Describe one ethical concern scientists or engineers must consider and explain how it could affect a project's outcome.
Example ethical concern: human/animal safety in experiments — could limit methods used or require extra safeguards and oversight.