SDS-PAGE gel results
Your fractions glowed green yesterday, but did you actually purify the target, or did contaminants ride along? What do the bands on your SDS-PAGE gel say?
Read an SDS-PAGE gel to judge the size and of your isolated .
- • You'll be able to estimate size against a marker lane.
- • You'll be able to judge and write a QC statement from a gel.
- On an SDS-PAGE gel, do smaller proteins travel farther down the gel or stay near the top? Why?
- If your target fraction shows one strong band plus three faint extra bands, is it pure? What do the extra bands represent?
- 1Read the gel-interpretation notes in the PLTW course shell and define the lane.
- 2Compare your fraction lanes to the marker to estimate your 's size.
- 3Decide which fraction is most pure based on how few extra bands it shows.
- 4Write one QC statement on whether the met the goal.
- 5Add your annotated gel reading to your Unit 4 PLTW tracker evidence.
🛠 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: SDS-PAGE sorts proteins by size alone because SDS erases charge and shape, so the band pattern reveals both your target's molecular weight and how many contaminants remain.
- 0-10Read gel-interpretation notes; define marker lane and band
- 10-28Annotate gel image: label marker lane, estimate target size
- 28-45Compare fraction lanes; count extra bands per lane
- 45-58Identify most-pure fraction; justify with band count
- 58-70Write QC statement: passed or failed goal with evidence
- 70-80Add annotated gel to tracker; preview Friday lab report
- • You collected fractions yesterday; today you find out what is actually in them.
- • SDS-PAGE separates proteins by size and makes every contaminant visible as a band.
- • A clean gel with one band says your worked; extra bands say it did not.
- • Gel interpretation is a core Lab SOPs skill tested on the 072130 WebXam.
- • SDS denatures proteins and gives all of them a uniform negative charge proportional to size.
- • Smaller proteins migrate farther through the gel matrix in a given time.
- • A pure target fraction shows one dominant band at the expected molecular weight.
GFP, chromatography, SDS-PAGE / gel interpretation, purity and QC. · SDS-PAGE gel results
Day 4 of this lesson. Open this exact section in myPLTW (find it in Clever, Microsoft sign-in), then do the work below.
Do this: Open Activity 4.1.4 in myPLTW and interpret your SDS-PAGE gel to judge size and of the isolated protein.
Mark the SDS-PAGE entry complete and attach your annotated gel image and QC statement.
Fraction-collection data should be done (Wednesday); annotated gel and QC statement due today.
Annotated SDS-PAGE gel with marker lane, size estimate, band counts, and QC statement submitted.
All PLTW activities are completed inside the PLTW course environment: this page only gives direction. Submit producibles on Schoology.
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.
GFP, chromatography, SDS-PAGE / gel interpretation, purity and QC. · SDS-PAGE gel results
Open Activity 4.1.4 in myPLTW and interpret your SDS-PAGE gel to judge size and of the isolated protein.
Fraction-collection data should be done (Wednesday); annotated gel and QC statement due today.
This is how Mr. Mendoza sees the class keeping pace with PLTW. Be honest, it only helps if it is accurate.
🎯 Read an SDS-PAGE gel to judge the size and of your isolated .
- Read the gel-interpretation notes in the PLTW course shell and define the lane.
- Compare your fraction lanes to the marker to estimate your 's size.
- Decide which fraction is most pure based on how few extra bands it shows.
- Write one QC statement on whether the met the goal.
- Add your annotated gel reading to your Unit 4 PLTW tracker evidence.
Data table: Annotated SDS-PAGE gel image with labeled marker lane, estimated size, band counts by fraction, most-pure fraction identified, and a QC statement.
Turn it in on Schoology using the checklist just below. Upload by 11:29 PM for full credit.
| Task | Who |
|---|---|
| Read the gel-interpretation notes in the PLTW course shell and define the lane. | _______ |
| Compare your fraction lanes to the marker to estimate your 's size. | _______ |
| Decide which fraction is most pure based on how few extra bands it shows. | _______ |
| Write one QC statement on whether the met the goal. | _______ |
| Add your annotated gel reading to your Unit 4 PLTW tracker evidence. | _______ |
Working solo? Put your own name in "Who" for every row.
- You'll be able to estimate size against a marker lane.
- You'll be able to judge and write a QC statement from a gel.
- 1Do thisRead an SDS-PAGE gel to judge the size and purity of your isolated protein.
- 2Use this resource
- 3Submit thisData table: Annotated SDS-PAGE gel image with labeled marker lane, estimated protein size, band counts by fraction, most-pure fraction identified, and a QC statement.
- 4Submit it here
- 1Open Clever.
- 2Microsoft (district) sign-in.
- 3Schoology and myPLTW are both in Clever.
Look for this assignment in Schoology: Genetics of Disease (Medical Interventions) › GFP, chromatography, SDS-PAGE / gel interpretation, purity and QC. › Data tableOpen Schoology
Learn it · deck, reading, and vocabulary▸
Tier 1 is the time-boxed teacher set for the block; Tier 2 adds scaffolded vocabulary, examples, and a reading routine; Tier 3 extends into careers and current biomedical applications.
Generated from this lesson's canonical data with a red-team citation check.
Students often think Students think proteins separate on the gel by their natural charge or shape, so the biggest or most-charged one moves fastest.. The trap: SDS coats every with a uniform negative charge and unfolds them, so charge and shape are erased. Separation is by size alone, and smaller proteins migrate farther because they slip through the gel matrix more easily.
How I read the gel: the marker (ladder) lane has bands of known molecular weights, so I use it as a ruler. Smaller proteins migrate farther down the gel, so I compare how far my band traveled to the marker to estimate size.
Reading:
- My target band lines up near the 27 kDa marker band, so I estimate the protein is about 27 kDa.
- Fraction 4 shows one strong band with almost no extra bands; fraction 2 shows several bands. So fraction 4 is the most pure.
QC statement: the purification met the purity goal, because the target fraction shows one dominant band at the expected size with very few contaminant bands, which is what a pure sample looks like.
| Lane | Bands seen | Estimated size | Note |
|---|---|---|---|
| Marker | Ladder of known sizes | reference | used as ruler |
| Fraction 2 | Several bands | mixed | impure, many contaminants |
| Fraction 4 | One dominant band | about 27 kDa | most pure, meets goal |
Also due today: Attach your annotated gel reading to your Unit 4 PLTW tracker and submit it to the course shell.
- 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, then give one example from what you actually did in SDS-PAGE gel results. 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.
Classroom documents for this lesson are posted in Schoology. Open Schoology and find each one by the name shown on its card.
Open this when the class reaches this activity and use it to complete the required lesson artifact.
Placement rationale
Matched and quality control by path:Medical-Interventions/Unit-4_When-Organs-Fail/4.1_Manufacturing-Human-Proteins; keywords:protein purification, gfp, . Score 150. 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 and quality control by path:Medical-Interventions/Unit-4_When-Organs-Fail/4.1_Manufacturing-Human-Proteins; keywords:protein purification, gfp, . Score 150. 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 and quality control by path:Medical-Interventions/Unit-4_When-Organs-Fail/4.1_Manufacturing-Human-Proteins; keywords:gfp, . Score 142. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
How to get there: open Clever and sign in with your Microsoft (district) account. You will find both Schoology and myPLTW right there in Clever. Turn in your work on Schoology; do the online activities in myPLTW.
Check yourself · commit, then reveal▸
Your best fraction shows one dark band at the expected molecular weight and two faint bands higher up (larger proteins). Is this fraction pure enough to call a success, and what are the two faint bands?
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▸
Finish the checklist before you handle any material.
- • No new chemical hazards today; gel image analysis is a paper or digital exercise.
- • If handling a physical stained gel, wear gloves as Coomassie stain is a skin irritant.
- • Dispose of any staining waste according to lab guidelines.
- 1Frame the guiding question and name your independent and dependent variables.
- 2Plan a method that would actually answer it, then get the plan checked before you start.
- 3Collect data carefully and record exactly what you observe before you interpret it.
- 4Build a tentative argument on a whiteboard: claim, evidence, reasoning.
- 5Argumentation session: present your board, question another group, and revise your claim.
- 6Write the final CER with your strongest evidence and one named limitation of the method.
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 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 Clever and sign in with your Microsoft (district) account. You will find both Schoology and myPLTW right there in Clever. Turn in your work on Schoology; do the online activities in myPLTW.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
Genetic Science Learning Center: Genetics basics and proteinsYou've passed Unit 2, so the optional extra-credit track is open. Complete reserved-unit work from home (virtual labs included) for extra credit, submitted on Schoology.
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 (Schoology for routine work) and confirmed.
- 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.