Grade: 12 Subject: Science Unit: Inquiry & Research SAT: ProblemSolving+DataAnalysis ACT: Science

Unit Checkpoint: Inquiry & Research

Instructions

  • Section A: Scientific Method & Design (5 questions)
  • Section B: Data Analysis (4 questions)
  • Section C: CER Response (1 question)

Section A: Scientific Method & Design

1. Which is the best example of a testable hypothesis?

A) Plants need sunlight to grow
B) Plants grown under blue light will produce more leaves than those under red light
C) Blue light is better for plants
D) Some plants grow better than others

2. In an experiment testing whether caffeine affects heart rate, caffeine consumption is the:

A) Dependent variable   B) Independent variable   C) Control variable   D) Confounding variable

3. Why is replication important in scientific research?

A) It saves time
B) It confirms results are reliable and not due to chance
C) It is required by law
D) It makes the experiment easier

4. A researcher wants to test whether a new fertilizer increases crop yield. Which experimental design is strongest?

A) Apply fertilizer to one field and measure yield
B) Compare yields from fertilized and unfertilized sections of the same field with random assignment
C) Ask farmers which fertilizer they prefer
D) Compare this year's yield to last year's

5. Peer review in scientific publishing ensures that:

A) All published research is correct
B) Research methods and conclusions are evaluated by experts
C) Only positive results are published
D) Research is kept confidential

Section B: Data Analysis

6. A study reports a p-value of 0.03. This means:

A) There is a 3% chance the hypothesis is true
B) There is a 3% probability of observing these results if the null hypothesis is true
C) 3% of participants showed the effect
D) The experiment was 97% accurate

7. Which graph type is most appropriate for showing how a variable changes over time?

A) Pie chart   B) Bar graph   C) Line graph   D) Scatter plot

8. A study finds r = 0.85 between hours of study and test scores. This indicates:

A) Studying causes high test scores
B) A strong positive correlation
C) A weak negative correlation
D) No relationship

9. Error bars on a graph typically represent:

A) Mistakes in the data
B) The range or variability of data
C) The maximum possible value
D) Time periods

Section C: CER Response

10. A student measured plant growth under three light conditions. Data shows: White light (15cm average), Blue light (18cm average), Red light (12cm average). Using the CER framework, write a complete scientific argument answering: "Which light color best promotes plant growth?"

  • Claim: (One sentence stating your conclusion)
  • Evidence: (Specific data that supports your claim)
  • Reasoning: (Explain WHY the evidence supports your claim using scientific principles)

Answer Key

Click to reveal
  1. B — It's specific, measurable, and includes both IV (light color) and DV (leaf production)
  2. B — Independent variable is manipulated by researcher; heart rate is the dependent variable
  3. B — Replication helps confirm results are consistent and not due to random variation
  4. B — Random assignment with control group eliminates confounding variables
  5. B — Peer review is quality control by expert evaluation, but doesn't guarantee correctness
  6. B — P-value indicates probability of results assuming null hypothesis is true
  7. C — Line graphs best show continuous change over time
  8. B — r = 0.85 is a strong positive correlation (close to 1.0)
  9. B — Error bars show data variability (often standard deviation or confidence interval)
  10. Sample CER Response:
    Claim: Blue light best promotes plant growth among the three light colors tested.
    Evidence: Plants grown under blue light averaged 18cm in height, compared to 15cm under white light and 12cm under red light.
    Reasoning: Blue light has a wavelength (450-495nm) that is efficiently absorbed by chlorophyll, the primary photosynthetic pigment. This wavelength corresponds to one of chlorophyll's absorption peaks, allowing for more efficient photosynthesis and thus greater growth. The 6cm difference between blue and red light represents a 50% increase in growth, indicating a significant effect of light wavelength on plant development.