Run the investigation
Open your materials, follow the steps, then turn in your work.
Conduct the C. elegans heavy-metal investigation and collect data on worm response.
1. Open your materials
Use the materials named in the first step below. Open lesson resources.
2. Start the work
Set up the exposure conditions and your control.
Show all 5 required steps
- Set up the exposure conditions and your control.
- Apply the heavy-metal treatments at planned concentrations.
- Observe and record worm movement or survival over time.
- Tabulate results for each condition.
- Note any unexpected observations during the run.
Lost your place? Back after a break? You are collecting live data. Rejoin at step 3: observe and record worm movement or survival for each condition on the same schedule, tabulate every dish including the control, and note anything unexpected.
Check your work before submitting
- Data is recorded for all treatment and control conditions.
- Observations are logged with consistent units.
Before lab work: read the safety rules
- Wear nitrile gloves and safety goggles at all times when handling heavy-metal solutions.
- Never pipette by mouth; use mechanical pipette aids only.
- Dispose of all heavy-metal waste in the designated container, not the sink.
- Wash hands thoroughly after removing gloves and before leaving the lab.
- Report any spills immediately to the teacher; do not attempt to clean chemical spills independently.
3. Turn in your work
DueCheck Schoology- Hand in
- Completed data table with results for all treatment concentrations and the control, consistent units, and notes on any unexpected observations.
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 Data table: Run the investigation
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: Heavy metals spread through the blood and jam enzymes that every cell needs, so one environmental exposure can injure many organ systems and force society to decide who is responsible for the harm. Today: 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.
Unit 2 guide: what to keep and use nextOptional: listen or watch a unit review▸
Need help? Warm-up, timing, and directions▸
💡 Big idea: 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.
- 0-10 review: handling heavy-metal solutions, disposal, PPE
- 10-20Set up exposure conditions and control; verify labels and concentrations
- 20-50Apply treatments; observe and record worm movement or survival at regular intervals
- 50-62Tabulate all results: condition, concentration, response metric, units
- 62-72Record any unexpected observations with description and time stamp
- 72-80Cleanup per protocol; submit completed
- • Your hypothesis is on paper; today you find out if the data supports it.
- • Following your protocol precisely is the difference between reliable data and noise.
- • Record everything, including observations you did not predict.
- • You will leave today with a complete ready for tomorrow's analysis.
- • Every condition in an experiment, including the control, must be documented with the same level of detail.
- • Unexpected observations are scientifically valuable and must be recorded, not ignored.
- • Dose-response relationships are central to toxicology and connect to Human Body Form, Function, and Pathophysiology WebXam content.
PLTW connection and today's work
Complete any lab-day check-in or data-entry prompt in Problem 2.3.1 Toxic Relationships (Lesson 2.3 Challenge Accepted) on myPLTW that accompanies today's C. elegans heavy-metal investigation; log it after tabulating your results.
Today's stopping point: Protocol task is done; today the lab task should show complete alongside your submitted data table.
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
Finish the assigned lab safely before starting extra practice.
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.
Heavy metals spread through the blood and jam enzymes that every cell needs, so one environmental exposure can injure many organ systems and force society to decide who is responsible for the harm.
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.
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 are exposed to different concentrations of a right now. What exactly do you record, and how often, so that tomorrow's graph actually means something?
What you already know: Heavy metals spread through the blood and jam enzymes that every cell needs, so one environmental exposure can injure many organ systems and force society to decide who is responsible for the harm.
New idea: 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.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Run the investigation. 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 run the investigation.
- 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: A physiology research team uses a tracker to confirm that variable definitions, measurements, and evidence files are complete before comparing results. Source: MedlinePlus: Evaluating Health Information.
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.
Biomedical evidence supports a conclusion only to the level allowed by the measurement, comparison, controls, source quality, and uncertainty in the investigation.
Limit: The classroom evidence supports the stated learning decision, not a real clinical diagnosis, causal conclusion, or treatment recommendation.
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.
Data is recorded for all treatment and control conditions.
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-2027-04-15 · Simulated classroom evidence scenario
Your role: anatomy and physiology consultant
Decision: Your team must decide what the evidence from run the investigation supports before submitting the labeled and result claim named on today's page.
- • Hold any before-and-after claim, since nobody recorded these same worms moving before the metal was ever added.
- • Record the control worms with the same care, units, and timing as every treated concentration today.
- • Spend your observation time on the treated worms, since the is not where the effect shows up.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the labeled and result claim.
Claim ceiling: Today's evidence supports a classroom claim about run the investigation. It cannot prove causation, diagnose a real patient, or justify action outside this room.
Reason for review: Your team must decide what the evidence from run the investigation supports before submitting the labeled and result claim named on today's page.
Context: Controlled investigations produce evidence only when every condition, including the control, is documented the same way and every unexpected observation is recorded, because raw data is worthless if you cannot trust how it was collected.
- • T1: Set up the exposure conditions and your control.
- • T2: Apply the heavy-metal treatments at planned concentrations.
- • T3: Observe and record worm movement or survival over time.
- • T4: Tabulate results for each condition.
- • T5: Note any unexpected observations during the run.
- • E1: Biomedical evidence supports a conclusion only to the level allowed by the measurement, comparison, controls, source quality, and uncertainty in the investigation.
- • E2: Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
- • E3: Data is recorded for all treatment and control conditions.
Measurements: Use only the measurements, units, graph, or counts supplied in today's task. No additional patient measurement is implied.
Figure finding: Teaching diagram for Run the investigation. Trace the labeled structure, movement, or system relationship that connects form to function. This is a teaching model, not patient or experimental data.
Uncertainty: This is a composite classroom scenario. Missing history, measurements, or confirmation tests remain unknown and limit the conclusion.
= 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.
- • The solution must address the stated need in run the investigation.
- • The decision must be supported by E1-E3.
- • The final product must make the success criteria visible.
- • Complete the work inside the 80-minute block.
- • Use only supplied or teacher-approved materials and evidence.
- • Do not trade , accessibility, or privacy for speed.
- • and evidence quality: must pass before scoring other criteria.
- • User need and effectiveness: highest scored criterion.
- • Time, cost, and ease of use: compare only after and effectiveness pass.
Test evidence: For each option, record the E1-E3 result that supports or fails each criterion. Do not assign a score without a named observation.
- Version or option tested
- Criterion met or missed
- Evidence ID and result
- Revision made
- Reason for the revision
- Need and user
- Criteria and constraints
- Chosen option and evidence
- Test result
- Revision and reason
Students often think Students often think the is the boring one, so it does not need the same careful observation as the treated groups.. The trap: That is the trap: the control is your baseline. If you record it less carefully, you have nothing trustworthy to compare the treatments against, and your whole dose-response claim collapses.
I recorded the number of worms still moving (out of 10) at each time point for every condition, then averaged my three runs. Keeping the same units and time points across all conditions, including the control, lets me compare them fairly.
Unexpected observation note:
In the 50 ppm plate, two worms stopped moving at 15 minutes but were moving again at 30 minutes. I recorded this rather than ignoring it, because recovery could mean the dose was sublethal or the worms were temporarily stunned.
| Copper (ppm) | Moving at 0 min | Moving at 15 min | Moving at 30 min |
|---|---|---|---|
| 0 (control) | 10 | 10 | 10 |
| 10 | 10 | 9 | 9 |
| 50 | 10 | 7 | 6 |
| 100 | 10 | 4 | 2 |
This model shows the level of evidence and organization needed to complete: Completes the data-collection target: a recorded data table covering every treatment concentration and the control, in consistent units, with notes on unexpected observations.
- Name the variables and include units.
- Enter observations without changing the raw values.
- Check labels, calculations, and patterns before interpreting the data.
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 data table 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 run the investigation. It cannot prove causation, diagnose a real patient, or justify action outside this room.
Why must you observe and record the control dish with the same care as the treated dishes?
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.
I can name the procedure's purpose and the evidence I will record. I can state today's specific hazards and the control for each. If this deck does not name them, I ask Mr. Mendoza before I touch anything. My data table is ready before materials are handled.
Finish the checklist before you handle any material.
- • Wear nitrile gloves and safety goggles at all times when handling heavy-metal solutions.
- • Never pipette by mouth; use mechanical pipette aids only.
- • Dispose of all heavy-metal waste in the designated container, not the sink.
- • Wash hands thoroughly after removing gloves and before leaving the lab.
- • Report any spills immediately to the teacher; do not attempt to clean chemical spills independently.
- 1Before materials are handled, identify the purpose, variables or comparison, controls, measurement units, and stop-work condition.
- 2Set up the exposure conditions and your control.
- 3Apply the heavy-metal treatments at planned concentrations.
- 4Observe and record worm movement or survival over time.
- 5Tabulate results for each condition.
- 6Note any unexpected observations during the run.
- 7Record each result in the prepared table before interpreting it. Mark missing, repeated, or invalid results truthfully.
- 8Complete the named cleanup and waste route, remove PPE safely, wash hands when required, and confirm the station is ready for the next group.
| Trial or sample ID | Independent condition | Measured result with units | Observation before interpretation | Quality-control note |
|---|---|---|---|---|
Before the procedure, predict the result and cite the rule behind the prediction.
After the procedure, compare the result with the prediction and name one limitation or source of uncertainty.
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.
Run your heavy-metal exposure on C. elegans, recording response data for every concentration and the control.
HHMI BioInteractive (preview; use assigned fallback if blocked)Use the submission route shown on today's today's page.
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.
- Error analysis and method · counts doubleName a specific limit of the method and how it moved your result, and compare what you predicted to what happened. "Human error" does not count; say what about the procedure or instrument caused it.
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