Concentration and serial dilution
Calculate concentrations and plan a serial dilution so you can prepare known sample strengths.
Four-step 1:10 serial dilution plan with concentration calculated at each step, plus a one-sentence prediction of signal change.
- 1Do thisCalculate concentrations and plan a serial dilution so you can prepare known sample strengths.
- 2Use this resource
- 3Submit thisData table: Four-step 1:10 serial dilution plan with concentration calculated at each step, plus a one-sentence prediction of signal change.
- 4Submit it here
- 1CMSD website. Go to clevelandmetroschools.org and click the Clever button.
- 2Clever. Clever opens. Sign in if it asks.
- 3Microsoft (district) login. Use your district Microsoft account (the one for school).
- 4Schoology. Open Schoology, then your class, then Assignments, and find the file named below.
The file to submit is named: Genetics of Disease (Medical Interventions) › Concentration, serial dilution, standard curves, antigen–antibody binding, direct vs. indirect ELISA. › Data tableOpen Schoology
Reasoning: connecting evidence to the claim
What separates sound reasoning from bad reasoning, and how do you check your own?
Reasoning is the part where you explain why your evidence supports your claim. It is the bridge. Without it, a claim and some data are just sitting next to each other; reasoning shows how the data leads to the conclusion, often using a scientific principle.
Good reasoning is logical (each step follows from the last), it actually uses your evidence (not just restates the claim), and it considers alternatives (could the data mean something else?). Bad reasoning leans on logical fallacies: jumping to conclusions, confusing correlation with causation, or attacking the person instead of the idea.
Check your own reasoning by trying to break it: state the opposite and see if your evidence rules it out. Ask “what would have to be true for me to be wrong?” If you cannot answer, your reasoning is not finished yet.
- • Logical: each step follows from the one before it.
- • Grounded: it uses your evidence, and names the principle that links it to the claim.
- • Fair: it considers other explanations and says why yours is better.
- • Self-checked: you tried to prove yourself wrong and could not.
- • Correlation is not causation: two things moving together does not mean one caused the other.
- • Hasty generalization: one case does not prove a rule.
- • Ad hominem: attacking the person, not their evidence.
Write the reasoning that links your evidence to your claim from earlier this week. Then write the strongest objection to it, and answer that objection.
- 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 — you open it through Schoology.
Minute-by-minute · 80-minute block
💡 Big idea: How do scientists use a series of known concentrations to measure the unknown concentration of a sample?
- 0-10 minDefine concentration and dilution factor in notebook; review C1V1 = C2V2 if needed
- 10-25 minWork through the serial dilution example: a 1:10 starting from a known stock, four steps
- 25-40 minPlan your own four-step 1:10 serial dilution; write concentration at each step; double-check math
- 40-55 minPredict how color/signal intensity would change down the series and explain why
- 55-70 minWrite one sentence connecting serial dilutions to standard curve construction
- 70-80 minPartner check: swap plans and verify each other's concentrations at every step
- • Every ELISA ever run in a clinical lab starts with a set of known standards; without them you have a signal but no meaning.
- • Serial dilution is one of the most fundamental techniques in all of biochemistry and molecular biology.
- • Today you master the math so that Wednesday's lab prep is a calculation you can do from memory.
- • Exit goal: a four-step dilution plan with correct concentrations at each step and a prediction sentence.
- 1Define concentration in your notebook as amount of substance per volume.
- 2Read the serial-dilution example, then write what a 1:10 dilution does to concentration.
- 3Plan a four-step 1:10 serial dilution and write the concentration at each step.
- 4Double-check your math: each step should be one-tenth of the step before.
- 5Predict how the color or signal would change down a dilution series.
- 6Write one sentence on why dilutions are useful for building a standard curve.
- • You will be able to define and calculate concentration.
- • You will be able to plan a serial dilution and predict each step's concentration.
- • You will be able to explain why dilutions matter for measurement.
- • Concentration is the amount of a substance dissolved in a given volume; a 1:10 dilution means one part sample to nine parts solvent.
- • A serial dilution creates a sequence of known concentrations by repeating the same dilution factor at each step.
- • A standard curve plots signal versus known concentration, allowing you to read off the concentration of any unknown sample.
Your PLTW work today
Concentration, serial dilution, standard curves, antigen–antibody binding, direct vs. indirect ELISA. · Concentration and serial dilution
Day 2 of this lesson. Open this exact section in myPLTW (reached through Schoology), then do the work below.
Do this: Open Activity 1.1.4 Serial Dilutions in myPLTW and work through the concentration and dilution calculation examples.
Write your four-step 1:10 serial dilution plan with concentration at each step and submit it.
Monday debate CER should be posted; dilution plan due today.
Dilution plan with four concentration values in notebook.
All PLTW activities are completed inside the PLTW course environment — this page only gives direction. Submit producibles on Schoology.
Today's PLTW tracker
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 on Schoology.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
Concentration, serial dilution, standard curves, antigen–antibody binding, direct vs. indirect ELISA. · Concentration and serial dilution
Open Activity 1.1.4 Serial Dilutions in myPLTW and work through the concentration and dilution calculation examples.
Monday debate CER should be posted; dilution plan due today.
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Calculate concentrations and plan a serial dilution so you can prepare known sample strengths.
- Define concentration in your notebook as amount of substance per volume.
- Read the serial-dilution example, then write what a 1:10 dilution does to concentration.
- Plan a four-step 1:10 serial dilution and write the concentration at each step.
- Double-check your math: each step should be one-tenth of the step before.
- Predict how the color or signal would change down a dilution series.
- Write one sentence on why dilutions are useful for building a standard curve.
Data table: Four-step 1:10 serial dilution plan with concentration calculated at each step, plus a one-sentence prediction of signal change.
Submit on SchoologyUpload by 11:29 PM for full credit.
| Task | Who |
|---|---|
| Define concentration in your notebook as amount of substance per volume. | _______ |
| Read the serial-dilution example, then write what a 1:10 dilution does to concentration. | _______ |
| Plan a four-step 1:10 serial dilution and write the concentration at each step. | _______ |
| Double-check your math: each step should be one-tenth of the step before. | _______ |
| Predict how the color or signal would change down a dilution series. | _______ |
| Write one sentence on why dilutions are useful for building a standard curve. | _______ |
Working solo? Put your own name in "Who" for every row.
- You will be able to define and calculate concentration.
- You will be able to plan a serial dilution and predict each step's concentration.
- You will be able to explain why dilutions matter for measurement.
Teacher-posted resources
Classroom documents for this lesson. Ones marked “Open the file” open right here; the rest are posted in Schoology. Use the label on each card to choose the right move.
Use this if you were absent, got stuck, or need another pass before you submit the lesson artifact.
Placement rationale
Matched ELISA model, dilution, standard curve by path:Medical-Interventions/Unit-1_How-to-Fight-Infection/1.1_The-Mystery-Infection; keywords:elisa, serial dilution, dilution. Score 154. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
Open this when the class reaches this activity and use it to complete the required lesson artifact.
Placement rationale
Matched ELISA model, dilution, standard curve by path:Medical-Interventions/Unit-1_How-to-Fight-Infection/1.1_The-Mystery-Infection; keywords:elisa, serial dilution. Score 146. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
Use this if you were absent, got stuck, or need another pass before you submit the lesson artifact.
Placement rationale
Matched ELISA model, dilution, standard curve by path:Medical-Interventions/Unit-1_How-to-Fight-Infection/1.1_The-Mystery-Infection; keywords:serial dilution, dilution. Score 142. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
How to get there: open the CMSD website, click Clever, sign in with your Microsoft (district) account, then open Schoology from Clever.
Lab & supplies
This unit's vocabulary
Tap the speaker to hear a term. Weekly vocabulary task: add two of these terms to your notebook glossary with a definition and an example in your own words.
WebXam practice
Cumulative WebXam review
A quick mixed-review pulling questions from earlier units plus today, so the WebXam material stays fresh.
Where this leads — careers
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.
What to do if you were absent
Today is individual PLTW work, so do exactly what we did in class, from home: complete the same PLTW target above, then submit your Data table.
Open Schoology (CMSD) and keep goingHow to get there: open the CMSD website, click Clever, sign in with your Microsoft (district) account, then open Schoology from Clever.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
HHMI BioInteractive- 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 (Schoology for routine work) and confirmed.
Drop your Mon, Sep 14, 2026 · Concentration and serial dilution here. Use a clear file name (your initials + project). Routine work still goes to Schoology (via the CMSD portal).
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