Data analysis and limitations
Open your materials, follow the steps, then turn in your work.
Analyze their investigation data and write a CER that acknowledges experimental limitations.
1. Open your materials
Use the materials named in the first step below. Open lesson resources.
2. Start the work
Graph worm response across concentrations.
Show all 5 required steps
- Graph worm response across concentrations.
- Make a claim about the effect of the heavy metal.
- Cite two data points as evidence.
- Add reasoning linking dose to response.
- List two limitations of your investigation.
Lost your place? Rejoining? You are writing your CER. Pick up at step 2: make one claim about the metal's effect, cite two specific data points as evidence, add reasoning that links dose to response, then list two real limitations.
Check your work before submitting
- CER includes claim, evidence, and reasoning.
- At least two real limitations are identified.
3. Turn in your work
DueCheck Schoology- Hand in
- Written CER with a dose-response claim, two specific data-point evidence entries, reasoning linking dose to worm response, and at least two limitations of the investigation.
How to submit and name your file
Use the submission route shown on today's today's page.
In Schoology, open your course and the assignment for this lesson. Attach your file, select Submit, and check that it appears in the submission.
PDF upload helpYou get two school days for every day you were absent, so this deadline moves with you.
Choose your Schoology section. Open only one assignment.
Check the section number beside Human Anatomy and Physiology in Schoology.
Assignment: Wk13 CER: Data analysis and limitations
Link will not open? Open Schoology, choose your section, and find the assignment title above.
How this lesson connects
Keep using what you learned last class: Every condition including the control is documented the same way so that the raw worm data can be trusted as evidence for a real dose-response effect rather than an artifact of careless observation. Today: Graphing reveals the dose-response pattern and a CER converts it into argument, so that stating limitations bounds the claim honestly and makes the conclusion more credible, not less.
Unit 2 guide: what to keep and use nextOptional: listen or watch a unit review▸
Need help? Warm-up, timing, and directions▸
💡 Big idea: Graphing reveals the dose-response pattern and a CER converts it into argument, so that stating limitations bounds the claim honestly and makes the conclusion more credible, not less.
- 0-12Graph worm response vs. concentration; label axes, title, and units
- 12-28Identify the dose-response trend; decide on a specific claim
- 28-48Write full CER: claim, two specific data-point evidence entries, reasoning linking dose to response
- 48-60Add limitations section: at least two real limitations with brief explanation
- 60-72: partner checks claim specificity, evidence values, and limitations
- 72-80Revise and submit CER
- • Your is full; now you have to turn numbers into a scientific argument.
- • A graph makes the dose-response pattern visible so you can write a precise claim.
- • Every real scientific paper includes a limitations section, and so will your CER.
- • By the end of class you will have a complete, peer-reviewed CER ready to submit.
- • A dose-response graph shows the relationship between concentration and biological effect.
- • Scientific claims must be supported by specific data, not general impressions.
- • Acknowledging limitations demonstrates scientific honesty and is required for the Evaluate Body Systems WebXam domain.
PLTW connection and today's work
Complete the data-analysis or CER reflection prompt in Problem 2.3.1 Toxic Relationships (Lesson 2.3 Challenge Accepted) on myPLTW associated with today's dose-response graph and CER; finish it before peer review.
Today's stopping point: Lab task is done; today the analysis task should show complete and your CER should be submitted.
PLTW activity titles identify the course connection. If your account will not open, use the posted materials for today and tell Mr. Mendoza. Do not mark an online activity complete unless you completed it.
Course connection
- Problem 2.3.1 Toxic Relationships
Use the turn-in directions at the top of this page. Do not create a second submission unless your teacher asks for one.
Show another explanation or a smaller first step
Need help? Choose a starting point
Lesson resources: reading, slides, and vocabulary▸
The deck carries the prior idea forward, lets you inspect an analogy, maps the rule to biology, and ends with the same evidence decision and exit ticket used on this page.
Generated from this lesson's canonical data with a red-team citation check.
Every condition including the control is documented the same way so that the raw worm data can be trusted as evidence for a real dose-response effect rather than an artifact of careless observation.
Graphing reveals the dose-response pattern and a CER converts it into argument, so that stating limitations bounds the claim honestly and makes the conclusion more credible, not less.
A research team lays out its question, variables, controls, sampling plan, measurement record, and analysis before deciding what the data support.
- Which variable is changed or compared?
- Which conditions and measurements must stay consistent?
- Which conclusion is inside the study's evidence boundary?
Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
A well-organized classroom study can still be limited by , measurement quality, confounding, and the population represented.
- • Question and variable cards map to the study design.
- • Control and measurement cards map to fair, reproducible data collection.
- • The conclusion card maps to a bounded claim supported by the analysis.
Driving question: Your worms moved less as the metal concentration rose. How do you prove that is a real dose-response effect and not luck, and where might your own experiment have fooled you?
What you already know: Every condition including the control is documented the same way so that the raw worm data can be trusted as evidence for a real dose-response effect rather than an artifact of careless observation.
New idea: Graphing reveals the dose-response pattern and a CER converts it into argument, so that stating limitations bounds the claim honestly and makes the conclusion more credible, not less.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Data analysis and limitations. Use it with E1-E3; it is a model or context image, not experimental or patient data. What to notice: Trace the labeled structure, movement, or system relationship that connects form to function.
- Observe or measure the relevant feature in today's lesson.
- Organize the observation with a stable evidence ID.
- Apply this rule: Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: Your worms moved less as the metal concentration rose. How do you prove that is a real dose-response effect and not luck, and where might your own experiment have fooled you?
What the evidence supports: E1-E3 and F1 support the daily take-home when the response meets the stated success criteria.
What it cannot prove: The package does not support claims beyond this lesson's or any real patient diagnosis.
Use it now: Choose one decision option. Cite E1 and E3, then explain how the rule connects the evidence to your choice.
Go further, optional: The source links below are optional enrichment. Every fact required for today's local evidence decision appears in this lesson package.
A planned study connects its question to defined variables, controls, sampling, measurement, and analysis so the resulting data can support a bounded and reproducible conclusion.
Limit: A statistical difference or trend does not automatically establish practical importance, causation, generalizability, or freedom from bias.
Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
Limit: A well-organized classroom study can still be limited by , measurement quality, confounding, and the population represented.
CER includes claim, evidence, and reasoning.
Limit: E3 defines the classroom product or success criterion. It is not independent scientific evidence and cannot justify a clinical or causal claim.
PLTW-HAP-2027-04-16 · Simulated classroom evidence scenario
Your role: anatomy and physiology consultant
Decision: Your team must decide what the evidence from today's lesson supports before submitting the claim-evidence-reasoning response named on today's page.
- • State the dose-response claim with specific data points and list the limitations that bound what your data proves.
- • Leave the limitations out, because naming a small will make your conclusion look weaker to the reader.
- • Hold the dose-response claim until a second independent run of the same concentrations repeats the pattern you saw.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the claim-evidence-reasoning response.
Claim ceiling: Today's evidence supports a classroom claim about today's lesson. It cannot prove causation, diagnose a real patient, or justify action outside this room.
= final volume / sample volume. New concentration = starting concentration / dilution factor.
Mix 1 mL of sample to a final volume of 10 mL. The is 10. A 100 mg/mL starting sample becomes 10 mg/mL.
Use the same volume units before dividing. Concentration keeps its original concentration unit.
Apply the same setup to one supplied dilution or dose. Show the factor, new value, units, and a reasonableness check.
Students often think Students often think naming limitations weakens their conclusion, so they hide the flaws in their experiment.. The trap: That is the trap: stating limitations is required scientific honesty and actually makes your argument stronger, because it shows you know exactly what your data can and cannot prove. Hiding a small does not make it disappear.
Parallel case (model only, not today's prompt): a different team tested how caffeine concentration affects the heart rate of Daphnia (water fleas) under a microscope.\n\nClaim: Increasing caffeine concentration raises Daphnia heart rate, showing a dose-response relationship.\n\nEvidence: In the 0 mg/L control, the average heart rate was 180 beats per minute. At 20 mg/L caffeine the average rose to 240 beats per minute, and the 10 mg/L group fell in between at about 210 beats per minute.\n\nReasoning: As the dose of caffeine rose, the biological effect (faster heartbeat) increased. This is what physiology predicts: caffeine is a stimulant that blocks the signals that normally slow the heart, so more caffeine drives more heartbeats per minute. The steady climb from control to 20 mg/L shows the effect scales with dose rather than jumping at random.\n\nLimitations:\n- Small sample size (only a few Daphnia per concentration) means one unusually fast or slow animal could shift the average a lot.\n- Heart rate was counted by eye while watching a fast, tiny heart, so the same beats could be tallied differently by different observers or on different trials.
This model shows the level of evidence and organization needed to complete: Parallel model of the analysis target: a dose-response CER that states a claim, cites two data points, reasons from dose to response, and names two real limitations. Model only. It does not answer today's copper-and-worms prompt.
- Write one defensible claim.
- Choose specific evidence that supports the claim.
- Explain the scientific rule that connects the evidence to the claim.
Keep the structure. Replace the question, facts, measurements, and evidence. Then recheck units, vocabulary, and whether the conclusion goes beyond the evidence.
Also due today: Submit your CER on Schoology.
- CER:
- Claim, Evidence, Reasoning: make a claim, back it with evidence, explain your reasoning.
- SOP:
- Standard Operating Procedure, the exact steps to follow (especially in a lab).
- Tracker:
- Your PLTW progress log where you record completed evidence.
- myPLTW:
- The PLTW course site where you do the online activities. Find it in Clever with your Microsoft sign-in, right next to Schoology.
Hand-picked readings, videos, and interactives for this lesson, all free and from authoritative open organizations (NIH, CDC, OpenStax, Khan Academy, PhET, HHMI, and more).
A fillable, Cornell-style notebook for Unit 2: Research Ready. Type your notes, cues, and summaries right in the PDF, or print it and write by hand. Each lesson page has a cue column, a notes column, and a summary box, plus dated lab-record pages you can turn in.
HBS Unit 2 notebook: Research Ready Fillable PDFCornell notes + lab recordsOpenVetted readings and references for this unit. Use them to prepare, to catch up if you were absent, or to go deeper on today's target.
Practice: try a question, then check your answer▸
Claim ceiling for this check: Today's evidence supports a classroom claim about today's lesson. It cannot prove causation, diagnose a real patient, or justify action outside this room.
Why does naming a limitation like a small sample size make your CER stronger rather than weaker?
Write an answer and pick a confidence to unlock the key.
Missed class or ready for more?▸
Run this before you touch the bench. It is built from the real lab procedure, so the decisions you make here are the ones you will make with the equipment in your hands.
What today's skills lead to. These are real health-science careers this course builds toward. Tap one to see, on the US Department of Labor's O*NET site, what the job actually involves, what it pays, and how fast it is growing.
Today is individual work you can do from home: complete the same target above, then submit your CER.
Go to Schoology to turn this in. Submit one PDF. Put your first and last name in the document header. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf. If you cannot get in, see Mr. Mendoza. Do not skip the work.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
CDC: Lead poisoning preventionYou've passed Unit 2, so the optional extra-credit track is open. Complete reserved-unit work from home, including virtual labs, for extra credit. Each item shows its correct submission route.
Open the extra-credit track- CompleteEvery required part of the artifact is present, nothing left blank.
- AccurateThe science and the data are correct and match the evidence.
- Scientific reasoningYou explain your claim with evidence and reasoning (CER), not just an answer.
- Professional communicationClear, organized, labeled, and written the way a clinician or scientist would.
- SubmittedGo to Schoology to turn this in. Submit one PDF. Put your first and last name in the document header. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf. If you cannot get in, see Mr. Mendoza. Do not skip the work.
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