Run the investigation
Safety gate · before any work
- 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.
Do now
Students will conduct the C. elegans heavy-metal investigation and collect data on worm response.
- Hand in
- Completed data table with results for all treatment concentrations and the control, consistent units, and notes on any unexpected observations.
- Where
- Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
You get two school days for every day you were absent, so this deadline moves with you.
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?
Students will conduct the C. elegans heavy-metal investigation and collect data on worm response.
- • Data is recorded for all treatment and control conditions.
- • Observations are logged with consistent units.
- Why must the control dish be observed exactly as carefully as the treated dishes?
- If a worm does something you did not expect, should you write it down or ignore it? Why?
- 1Set up the exposure conditions and your control.
- 2Apply the heavy-metal treatments at planned concentrations.
- 3Observe and record worm movement or survival over time.
- 4Tabulate results for each condition.
- 5Note any unexpected observations during the run.
What did this day actually feel like?
Run the investigation
LAB Our own design, our own protocol, multiple treatment concentrations. This is the first time all semester the experiment was ours rather than handed to us.
One concentration gave results that made no sense until we realized we had run it second to last and the samples had been sitting. Time was an uncontrolled variable and we did not see it coming.
Turned in: completed data table → Data Tables folder
Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.
The same day, drawn.
Our own design, our own protocol, multiple treatment concentrations. This is the first time all semester the experiment was ours rather than handed to us.
TEAMMATE
We ran that concentration second to last. It had been sitting. Time was a variable and we never controlled it.
Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.
🛠 Get unstuck · pick your level
Lab day: Tier 1 is the whole class at the bench. No extension today.
🔑 Today's words · 5
Tap a word in the lesson for a plain meaning and one example. Recycled into next week's Do-Now.
Do the work · 80-minute blockfirst 5 min = hook▸
💡 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 /Physiology/Pathophysiology WebXam content.
Unit 2.3 Challenge Accepted: Open-ended C. elegans/heavy metal investigation or validated simulation; data and conclusions. · Run the investigation
Day 3 of this lesson. Open this exact section in myPLTW (find it in Clever, Microsoft sign-in), then do the work below.
Do this: Complete any lab-day check-in or data-entry prompt in Lesson 2.3 Challenge Accepted on myPLTW that accompanies today's C. elegans heavy-metal investigation; log it after tabulating your results.
Mark the lab-day task complete in myPLTW after submitting your completed .
Protocol task is done; today the lab task should show complete alongside your submitted .
Note or screenshot of completion status for your tracker.
The official PLTW activity stays inside myPLTW. If myPLTW will not open, use F1 and E1-E3 on this page to complete today's local evidence decision, then make up the official activity when access returns. Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
Check things off as you work, then submit. This tells Mr. Mendoza how you're doing so he can help the class. It does not replace turning in your producible through the submission route shown below.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
Unit 2.3 Challenge Accepted: Open-ended C. elegans/heavy metal investigation or validated simulation; data and conclusions. · Run the investigation
Complete any lab-day check-in or data-entry prompt in Lesson 2.3 Challenge Accepted on myPLTW that accompanies today's C. elegans heavy-metal investigation; log it after tabulating your results.
Protocol task is done; today the lab task should show complete alongside your submitted .
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Students will conduct the C. elegans heavy-metal investigation and collect data on worm response.
- 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.
Data table: Completed with results for all treatment concentrations and the control, consistent units, and notes on any unexpected observations.
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Use the checklist just below and upload by 11:29 PM for full credit. Absent with an excused absence? You get two school days for every day you were absent, so this deadline moves with you.
| Task | Who |
|---|---|
| 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. | _______ |
Working solo? Put your own name in "Who" for every row.
- Data is recorded for all treatment and control conditions.
- Observations are logged with consistent units.
- 1Do thisStudents will conduct the C. elegans heavy-metal investigation and collect data on worm response.
- 2Use this resource
- 3Submit thisData table: Completed data table with results for all treatment concentrations and the control, consistent units, and notes on any unexpected observations.
- 4Submit it here
- 1Open the drop folder.
- 2Sign in with your district Microsoft account, not a personal one.
- 3Upload the file, named Lastname_Firstname__Assignment Title.
- 4Your own upload panel says Uploaded with a green check: that is your receipt.
Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not. Human Anatomy & Physiology (Human Body Systems) › Unit 2.3 Challenge Accepted: Open-ended C. elegans/heavy metal investigation or validated simulation; data and conclusions. › Data tableOpen the drop folder
Learn it · deck, reading, 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 detective board holds observations, possible explanations, and one next question.
- Which notes are direct observations?
- Which notes are explanations?
- What new evidence would separate the explanations?
Keep observations separate from explanations, then collect the evidence that can distinguish the options.
Biomedical investigations use controlled procedures and validated measurements, not intuition alone.
- • Board notes map to E1-E3.
- • Possible explanations map to the decision options.
- • The next question maps to the evidence-based action.
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: Keep observations separate from explanations, then collect the evidence that can distinguish the options.
- 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.
- • : A dense metallic element such as lead, mercury, or arsenic that is toxic to the body even at low amounts and can build up over time.
- • toxicology: The science of how chemicals and other substances cause harm to living things, including the dose at which they become dangerous.
- • hypothesis: A testable, falsifiable prediction about how variables relate, written so an experiment can support it or prove it wrong.
- • : An organized grid of rows and columns used to record measurements and observations clearly so they can be compared and analyzed.
- • graph: A visual display of data, such as a bar, line, or scatter plot, that makes patterns and relationships easier to see than a table of numbers.
- • limitation: A weakness or boundary of a study, design, or method that restricts how far its results can be trusted or applied.
- • conclusion: The closing part of an investigation where you state whether the evidence supported your hypothesis and explain what the results mean.
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.
Every condition in an experiment, including the control, must be documented with the same level of detail.
Limit: E1 supplies context or an observation; it does not by itself establish the explanation.
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.
Limit: E2 is a teaching statement or comparison and must be checked against the task evidence.
Data is recorded for all treatment and control conditions.
Limit: E3 supports only the result or product criterion named here; it cannot justify a broader 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 the lesson page.
- • Select the option best supported by E1-E3.
- • Select a reasonable alternative and name the evidence it would require.
- • Delay the claim because the evidence does not distinguish the options.
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: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Run the investigation. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.
Reason for review: Your team must decide what the evidence from Run the investigation supports before submitting the labeled and result claim named on the lesson 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: Every condition in an experiment, including the control, must be documented with the same level of detail.
- • E2: 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.
- • 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.
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 the class site, or hand it to Mr. Mendoza in class.
- 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.
Tap the speaker to hear a term. Add two of these to your notebook glossary with a definition and an example in your own words.
Pick just 2 or 3 words from today and make them yours: write what each one means in your own words, name the context clue or evidence that helped, then give one example from what you actually did in Run the investigation. Try your own words first; the glossary is there if you get stuck. This is voluntary and counts as extra credit, so keep it short.
Saved on this device. Show Mr. Mendoza or add these to your notebook glossary to claim the extra credit.
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.
Check yourself · commit, then reveal▸
Claim ceiling for this check: The supplied lesson evidence can support an observation, pattern, classroom mechanism, or next-step decision about Run the investigation. It cannot by itself prove causation, establish a real clinical diagnosis, or justify action outside this classroom task.
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.
Fast retrieval with instant answers, not the commit-then-reveal check above. Try each from memory first: write what you remember about the earlier units, then check yourself here.
Go further and get help▸
I can name the procedure's purpose and the evidence I will record. I can identify each named hazard and the control that reduces it: Wear nitrile gloves and safety goggles at all times when handling heavy-metal solutions. 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)Then submit your Data table. Turn this in at the drop folder with your district Microsoft sign-in, or hand it to Mr. Mendoza in class. Both count as submitted. Doing the activity in myPLTW does not.
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.
- SubmittedTurned in the right way, on the class site or handed to Mr. Mendoza in class, and confirmed. Not in Schoology: that is where the report-card grade appears later.
- 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.