Bone repair and repair tech
Open your materials, follow the steps, then turn in your work.
Explain the stages of bone repair and evaluate one repair technology with a CER.
1. Open your materials
Use the materials named in the first step below. Open lesson resources.
2. Start the work
Read the notes on the bone-healing stages: hematoma, soft callus, hard callus, remodeling.
Show all 5 required steps
- Read the notes on the bone-healing stages: hematoma, soft callus, hard callus, remodeling.
- Match each stage to the bone cells most active during it.
- Research one repair technology (casting, plates, or bone graft) from the PLTW task.
- Write a CER claiming when that technology is the best choice.
- Submit your repair-stage diagram and technology CER.
Lost your place? Lost the thread? If your four-stage diagram is not done, do step 1 and list hematoma, soft callus, hard callus, remodeling in order. If the diagram is done, go to step 3, research one repair technology, and write your CER for when it is the best choice.
Check your work before submitting
- You can sequence the stages of bone repair.
- You can justify when a given repair technology is appropriate.
3. Turn in your work
DueCheck Schoology- Hand in
- Repair-stage timeline diagram (four stages with active cells labeled) plus a CER arguing when a specific repair technology is the best choice.
How to submit and name your file
Submit diagram and CER as a single combined document.
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: Wk5 CER: Bone repair and repair tech
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: Because each type of force leaves a distinct break pattern, you can read a fracture from imaging and reconstruct how the injury happened, so classification is evidence, not labeling. Today: Because bone repair runs through a fixed four-stage sequence driven by osteoblasts and osteoclasts, doctors choose a repair technology by matching it to the stage and severity that need support, so fracture care follows the biology.
Unit 1 guide: what to keep and use nextOptional: listen or watch a unit review▸
Need help? Warm-up, timing, and directions▸
💡 Big idea: Because bone repair runs through a fixed four-stage sequence driven by osteoblasts and osteoclasts, doctors choose a repair technology by matching it to the stage and severity that need support, so care follows the biology.
- 0-8Intro: connect Tuesday cells to repair stages
- 8-25Notes: four repair stages with cell activity at each
- 25-45PLTW task: research one repair technology
- 45-62Draw and label repair-stage timeline diagram
- 62-75Write CER: when is your chosen technology the best choice?
- 75-80Submit diagram and CER; preview Friday evidence day
- • Yesterday you classified fractures. Today you learn what happens after the break. Bone heals, but only if the conditions are right.
- • The four stages of healing map directly onto the bone cells you learned Tuesday. This is the payoff of that chart.
- • You will also evaluate one repair technology and write a CER claiming when it is the best option. Your CER needs a specific type as the patient scenario.
- • This content is high-yield for the Human and Physiology emphasis on the WebXam. Know the stage names and the cells involved.
- • The four stages of bone repair: hematoma formation, fibrocartilaginous callus (soft callus), bony callus (hard callus), and bone remodeling.
- • Osteoblasts are most active during callus formation; osteoclasts dominate the remodeling stage.
- • Repair technologies range from immobilization (casting/splinting) to internal fixation (plates, screws, rods) to biological augmentation (bone graft).
PLTW connection and today's work
Complete the bone-repair and repair-technology task in Project 1.1.6 Break a Leg (Lesson 1.1 Beginning With Bones) on myPLTW; work through all screens during the 25-45 minute window.
Today's stopping point: Fracture task is done; today the bone-repair task should show complete and your diagram and 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
- Project 1.1.6 Break a Leg
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.
Because each type of force leaves a distinct break pattern, you can read a from imaging and reconstruct how the injury happened, so classification is evidence, not labeling.
Because bone repair runs through a fixed four-stage sequence driven by osteoblasts and osteoclasts, doctors choose a repair technology by matching it to the stage and severity that need support, so care follows the biology.
A library keeps a master plan protected while working copies guide production at different stations.
- Why protect the master copy?
- What information moves?
- Where can an error change the final product?
Stored information can be copied, read, and converted into a functional product.
Genes are regulated biological sequences, not conscious instructions, and one gene rarely determines a whole trait alone.
- • Master plan maps to DNA.
- • Working copy maps to RNA.
- • Production output maps to or a regulated cell function.
Driving question: A clean forearm crack gets a cast; a shattered comminuted femur gets a metal rod and screws. Both are 'broken bones,' so why does one get plaster and the other get surgery?
What you already know: Because each type of force leaves a distinct break pattern, you can read a from imaging and reconstruct how the injury happened, so classification is evidence, not labeling.
New idea: Because bone repair runs through a fixed four-stage sequence driven by osteoblasts and osteoclasts, doctors choose a repair technology by matching it to the stage and severity that need support, so care follows the biology.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Bone repair and repair tech. 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: Stored information can be copied, read, and converted into a functional product.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: A clean forearm crack gets a cast; a shattered comminuted femur gets a metal rod and screws. Both are 'broken bones,' so why does one get plaster and the other get surgery?
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 bone-building cell that produces and lays down new bone matrix, helping bones grow, heal, and stay strong.
- • : A large bone cell that breaks down and removes old bone , helping the body remodel bone and release stored calcium.
- • : The dense, hard outer layer of bone, built from tightly packed cylindrical units, that gives the skeleton most of its strength and protection.
- • : The lightweight inner bone made of a lattice of bony struts called trabeculae, often filled with marrow and found at the ends of long bones.
- • : A break or crack in a bone, ranging from a thin hairline crack to a complete break into separate pieces.
- • : The place where two or more bones meet, often allowing movement, with and ligaments holding the bones together.
- • : A tough band of that connects bone to bone, holding joints together and keeping them stable.
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.
Musculoskeletal function depends on the interaction of structure, force, joints, neural activation, and loading history, so one model or measurement captures only part of performance.
Limit: A classroom model or movement measure cannot diagnose an injury or prescribe .
Stored information can be copied, read, and converted into a functional product.
Limit: Genes are regulated biological sequences, not conscious instructions, and one gene rarely determines a whole trait alone.
You can sequence the stages of bone repair.
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-2027-02-18 · 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.
- • Match the repair technology to the 's stage and severity, so a cast fits a clean crack.
- • Explain the healing as the two broken ends fusing straight back into finished bone, like glue.
- • Wait for a later check of the callus before judging the repair, because one look cannot show progress.
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.
Reason for review: Your team must decide what the evidence from today's lesson supports before submitting the claim-evidence-reasoning response named on today's page.
Context: Bone heals through a fixed four-stage sequence run by the same build-and-remove cells, so repair technology is matched to the by asking which stage needs support, not by picking the fanciest option.
- • T1: Read the notes on the bone-healing stages: hematoma, soft callus, hard callus, remodeling.
- • T2: Match each stage to the bone cells most active during it.
- • T3: Research one repair technology (casting, plates, or bone graft) from the PLTW task.
- • T4: Write a CER claiming when that technology is the best choice.
- • T5: Submit your repair-stage diagram and technology CER.
- • E1: Musculoskeletal function depends on the interaction of structure, force, joints, neural activation, and loading history, so one model or measurement captures only part of performance.
- • E2: Stored information can be copied, read, and converted into a functional product.
- • E3: You can sequence the stages of bone repair.
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 Bone repair and repair tech. 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.
Mean = sum of values / number of values. Median = middle ordered value. Range = maximum - minimum.
For 2, 4, 4, and 10: mean = 20 / 4 = 5, median = 4, and range = 10 - 2 = 8.
Mean, median, and range keep the measurement unit. Order the values before finding the median.
Calculate the requested summary for today's supplied values, then write what it reveals and what it hides.
Students often think Students picture bone healing like glue, where the two broken ends simply fuse straight back together into finished bone.. The trap: Healing goes through intermediates: first a blood clot (hematoma), then a soft callus, then a hard bony callus, and only then remodeling back to normal shape, because the body has to bridge the gap with temporary before osteoblasts can lay down real bone. Skipping the callus stages in your mental model makes the timeline and the technology choices impossible to explain.
Parallel case: a torn anterior cruciate ligament (ACL) in the knee. This models the same CER format used for repair-technology decisions, using a soft-tissue injury instead of a broken bone, so the reasoning steps are visible without giving away the fracture answer.\n\nRepair-stage timeline (four stages, with active cells):\n1. Inflammation: blood vessels at the tear leak fluid and a clot forms; inflammatory cells such as neutrophils and macrophages clear damaged tissue and debris.\n2. Proliferation: fibroblasts move into the wound and lay down new type III collagen, forming soft, disorganized scar tissue that loosely bridges the gap.\n3. Remodeling begins: fibroblasts replace the weak type III collagen with stronger, more organized type I collagen, and the fibers start to line up along the direction of stress.\n4. Maturation: the collagen network continues to align and strengthen over months, but ligament scar tissue rarely regains the full strength or blood supply of the original ligament.\n\nTechnology CER:\nClaim: For a young, active athlete with a fully torn ACL who wants to return to cutting and pivoting sports, surgical reconstruction with a tendon graft is the best repair technology.\nEvidence: A fully torn ACL has poor blood supply and does not reliably heal back to a stable, load-bearing ligament on its own. A brace and physical therapy can restore strength for daily activity, but the natural four-stage healing above leaves scar tissue that is weaker and less organized than the original. Reconstruction replaces the torn ligament with a graft that the body can integrate, restoring joint stability for high-demand movement.\nReasoning: Because this patient needs the knee to resist twisting forces during sports, the goal is a stable, load-bearing ligament, which unaided healing cannot dependably provide. A brace alone would leave the joint unstable and raise the risk of further cartilage damage, so the added risk of surgery is justified by the stability the athlete needs, making reconstruction the best fit for this case.
| Stage | What forms | Most active cells |
|---|---|---|
| 1 Hematoma | Blood clot at break | Inflammatory cells |
| 2 Soft callus | Collagen and cartilage bridge | Osteoblasts, chondroblasts |
| 3 Hard callus | Spongy bone | Osteoblasts |
| 4 Remodeling | Final shaped bone | Osteoclasts and osteoblasts |
This model shows the level of evidence and organization needed to complete: A four-stage timeline of soft-tissue (ligament) healing with the active repair cells labeled, plus a claim-evidence-reasoning argument for when a chosen repair technology is the best choice. This models the CER format for a different injury so it does not answer the fracture 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 diagram and CER as a single combined document.
- 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 Bone repair and repair tech. 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 1: Road to Rehabilitation. 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 1 notebook: Road to Rehabilitation 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.
During which stage of bone repair are osteoblasts most active, and during which stage do osteoclasts take over? Explain what each is doing.
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.
Missed class or ready for more?▸
You do not need to turn in the pre-lab simulation. It is a Feb 17 resource, not a Feb 18 required step.
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:
MedlinePlus: Bone Diseases and Fractures- 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.
This week
My Progress dashboard