Your Weeks Work packet
The packet tells this week's story day by day, explains every term on labeled reference pages, and lists each task with its deadline. Open it before you start today's work. The mind map shows how the whole unit fits together, with the tested ideas in red. Your Unit 1 Take-Home Exam is handed out Friday, October 2 and due Monday, October 5 at the start of class. It replaces the in-class Unit 1 Test printed in the packet, so ignore the packet's 40-minute and pencil instructions for the test.
Analyze histology evidence
This page has four parts, in the order you use them. Part 1 is what you need to know. Part 2 says what to do, in plain English. Part 3 shows the work done once on a case that is not yours. Part 4 is your own work and where to turn it in.
Open your materials, follow the steps, then turn in your work.
Interpret tissue and heart observations with a CER and evaluate identification limits.
Case background, evidence, and file details▸
How today connects to the case
Where: Statik Sound, a neighborhood recording studio. Who: Marcus Bell, 34, owner and producer of Statik Sound, found on the studio floor behind the mixing console on a Monday morning by his business partner.
The scene in our room is the scene in the case: tape at the door, the outline and torso behind the console, the lower body beneath a fallen speaker cabinet and an acoustic moving blanket. Responders left the scene as found, pending investigation.
Your job: By Day 18 your team names the manner and cause of death and backs each one with at least four exhibits across three different evidence types. Every claim stops where the evidence stops.
Today you will read the case's tissue slides: learn the four tissue families, then make the histology calls that explain yesterday's organ findings.
Remember: Organs are built from four tissue families. Disease and injury change the weave, and the microscope reads the weave.
- Activity 1.2.4 Histology
This John Hay case practices skills connected to the PLTW activity above. Follow today's directions for the assigned work.
Missed class? Open today's worksheet and briefing. Use simulated data only if the worksheet or Mr. Mendoza provides it, and label it "Simulated data." If a required measurement or file is missing, ask Mr. Mendoza. Do not invent results.
Evidence released today
- Exhibit 016 · Reference slide: healthy pancreatic islet (200x) · Medical thread
- Exhibit 017 · Case slide: Pancreatic islet crowded by immune cells: the autoimmune attack that destroys insulin-making beta cells in type 1 diabetes. (200x) · Medical thread
- Exhibit 018 · Case slide: kidney, osmotic change (100x) · Medical thread
- Exhibit 019 · Case slide: wound margin, vital response (200x) · Medical thread
Exhibit means one numbered piece of evidence. Thread means the team lane it belongs to (Scene, Trace, Serology and DNA, Toxicology, Medical Examiner, Records). Exhibits are handed out on paper in class on the day they are released, and the same files are attached to that day's Schoology assignment.
Notebook reminders
- Investigation Day 14 pack (paper in class; the PDF is above and on the Schoology assignment)
- Investigative Notebook: Histology call cards organizer
- Investigative Notebook: Logic tree update
- Investigative Notebook: Day 14 Cornell page
Daily Evidence Sheet, Day 14: the worksheet linked at the top of this page, every Part complete.
Submit one PDF of your Daily Evidence Sheet to Wk5 D14 · The Fabric Under the Lens (PLTW 1.2.4).
Schoology assignment: Wk5 D14 · The Fabric Under the Lens (PLTW 1.2.4)
Before the hands-on lab
- Histology: Four Tissue Types simulationComplete this simulation before you begin the hands-on work.
What the evidence can and cannot prove
- Classroom evidence supports a classroom finding. It cannot convict a real person or diagnose a real patient.
- A hair consistent with a person proves a hair like theirs was present, not that the person was, and never when.
- A fingerprint proves touch, not when or why. A pattern class narrows a crowd; only minutiae can name one finger.
- A presumptive test says maybe. Only a confirmatory test says blood, and only DNA says whose.
- One value outside its reference range is a flag, not a verdict.
Make only the claims your evidence supports. Explain what you still cannot tell.
Optional: listen or watch a unit review▸
Part 1 of 4 · Background and definitions▸
💡 Big idea: A pathologist diagnoses disease by comparing to a normal reference because appearance varies between people, so disease is recognized as deviation from normal rather than from any single slide.
- • Comparison to reference images is required because appearance varies between individuals; diagnosis is based on deviation from normal, not on a single observation.
- • Two variables that affect slide interpretation are the quality of the staining (how well the dye bound to structures) and the thickness and angle of the section.
- • Microscopy alone cannot determine ; it must be combined with gross , clinical history, and toxicology for a complete picture.
You must record magnification on every microscopy sketch because apparent size means nothing without it, so an unlabeled sketch cannot be trusted or compared by another scientist.
A pathologist diagnoses disease by comparing to a normal reference because appearance varies between people, so disease is recognized as deviation from normal rather than from any single slide.
Driving question: Looking at your own sketches next to a reference image of healthy tissue, what deviation would you point to as possible evidence of what killed this person?
What you already know: You must record magnification on every microscopy sketch because apparent size means nothing without it, so an unlabeled sketch cannot be trusted or compared by another scientist.
New idea: A pathologist diagnoses disease by comparing to a normal reference because appearance varies between people, so disease is recognized as deviation from normal rather than from any single slide.
- Observe or measure the relevant feature in analyze evidence.
- Organize the observation with a stable evidence ID.
- Apply this rule: Structure creates possibilities and limits for function.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: Looking at your own sketches next to a reference image of healthy tissue, what deviation would you point to as possible evidence of what killed this person?
What the evidence supports: E1 to E3 and the figure 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.
- • : The body's ongoing process of keeping internal conditions like temperature, blood sugar, and pH steady despite changes in the outside environment.
- • : A group of similar cells working together to perform a shared function, such as muscle, nerve, or .
- • : A group of organs that work together to carry out a major body function, such as the digestive or circulatory system.
- • toxicology: The science of how chemicals and other substances cause harm to living things, including the dose at which they become dangerous.
- • : The study of the microscopic structure of tissues, examining thin stained slices under a microscope to see how cells are arranged.
- • : The specific physiological breakdown inside the body that directly ends life, such as a fatal heart rhythm or blood loss, separate from the underlying cause.
Use it now: Choose one decision option. Cite E1 and E3, then explain how the rule connects the evidence to your choice. This is thinking practice for the one turn-in named under Turn in, not a second submission.
Go further, optional: The source links below are optional enrichment. Every fact required for today's local evidence decision appears in this lesson package.
Standard anatomical terms describe location and structure precisely, while physiology describes function; connecting levels from cells to tissues, organs, and systems supports a bounded explanation.
Limit: A classroom map or organization model simplifies three-dimensional variation and cannot diagnose injury or disease.
Structure creates possibilities and limits for function.
Limit: Living tissues adapt and interact with other systems; a metal tool does not.
You can interpret against references.
Limit: E3 defines the classroom product or success criterion. It is not independent scientific evidence and cannot justify a clinical or causal claim.
Today's decision · Simulated classroom evidence scenario
Your role: biomedical investigator
Decision: Your team must decide what the evidence from analyze evidence supports before submitting the claim-evidence-reasoning response named on today's page.
- • Point to the odd-looking spot on my slide and call it diseased, because damaged looks wrong the moment you see it.
- • Hold my interpretation until a second, cleaner section is examined, because a thick cut or bad stain can imitate disease.
- • Name the deviation by holding my sketch against the healthy reference image, since disease shows up as a difference from normal.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Use it inside the one turn-in named under Turn in; it is not a separate submission.
Claim ceiling: Today's evidence supports a classroom claim about analyze evidence. 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 analyze evidence supports before submitting the claim-evidence-reasoning response named on today's page.
Context: Diagnosis works by comparison to normal, so a pathologist recognizes disease by what is missing or distorted, not by any single observation alone.
- • T1: Compare your sketches to reference images.
- • T2: Write a CER: what damage could indicate ?
- • T3: Relate one finding to a possible pathology.
- • T4: Identify two variables that affect slide interpretation.
- • T5: State one limitation of microscopy for determining .
- • E1: Standard anatomical terms describe location and structure precisely, while physiology describes function; connecting levels from cells to tissues, organs, and systems supports a bounded explanation.
- • E2: Structure creates possibilities and limits for function.
- • E3: You can interpret against references.
Measurements: No patient measurement is supplied unless it appears explicitly in E1-E3 or F1. Do not invent a value.
Figure finding: Two microscope fields drawn as circles at the same magnification with a scale bar in each. The left field, Reference slide, shows generic drawn cell outlines. The right field, Case exhibit, is blank except for a faint outline and the words sketch what you see. An arrow labeled compare points from left to right.
Uncertainty: This is a composite classroom scenario. Missing history, measurements, or confirmation tests remain unknown and limit the conclusion.
Students often think an experienced pathologist can look at one slide alone and just know it is diseased, the way you know a bruise when you see one. The trap: appearance varies between individuals, so diagnosis is based on deviation from normal reference tissue, not a single observation; a bad stain or a thick section can mimic disease if you have nothing to compare against.
- 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 Analyze histology evidence. 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.
Part 2 of 4 · Directions in plain English▸
2.1 Open your materials
Before the lab: Complete Histology: Four Tissue Types simulation.
2.2 Start the work
Compare your tissue sketches to reference histology images.
Show all 5 required steps
- Compare your tissue sketches to reference histology images.
- Write a CER: what tissue damage could indicate cause of death?
- Relate one tissue finding to a possible pathology.
- Identify two variables that affect slide interpretation.
- State one limitation of microscopy for determining cause of death.
Lost your place? You are analyzing your lab evidence. Check that you have compared your sketches to reference images (step 1) and written a CER on what damage could indicate cause of death (step 2), then finish naming two variables that affect slide interpretation (step 4) and one limitation of microscopy (step 5).
- 0:00Return the lab notebooks; display reference images for all four types
- 0:10Guided comparison: walk through one type together, identifying normal vs. abnormal features
- 0:22Students compare their four sketches to references; annotate differences directly on their notebook sketches
- 0:38-pathology connection: for one tissue in today's exhibits, research and note one associated pathology
- 0:52CER writing: claim about what damage could indicate , evidence from comparison, reasoning from pathology connection
- 1:05List two slide-interpretation variables and one limitation of microscopy alone; preview the submission
- • Yesterday you looked at slides and sketched what you saw. Today you figure out what it means. That requires a reference, something to compare your observation to.
- • A pathologist does not just look at a slide and announce what is wrong. They compare every structure to what it should look like in a healthy sample. When something is thicker, thinner, misshapen, or missing, that is the finding.
- • We are going to do the same thing. You will compare your lab sketches to reference images and ask: does this look normal? If not, what could have caused the deviation?
- • Your CER today is your argument. What does the evidence suggest about how this person might have died? You will also connect one tissue finding to a possible pathology.
PLTW connection and today's work
In myPLTW, open Lesson 1.2 Master the Morgue and go back to Activity 1.2.4 Histology. Finish its analysis section using your reference comparisons.
Today's stopping point: You examined slides and the heart last class. By the end of today your CER and reference comparison annotations should both be done.
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.
Use the turn-in directions in Part 4 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
Part 3 of 4 · Worked example▸
This is a parallel case, not your own. Read it for the order of the work, then do your own in Part 4.
Claim: The latent print lifted from the scene could indicate that this individual touched the surface before the incident.
Evidence: Compared to a known reference print taken directly from the individual, the latent print showed the same pattern of ridge endings and bifurcations in the same relative positions, which are the features examiners use to match prints.
Reasoning: Identification is based on agreement between an unknown sample and a known reference, so the side-by-side comparison is what makes the matching ridge features meaningful. A shared arrangement of ridge endings and bifurcations is consistent with both prints coming from the same finger.
Limitation: A partial or smudged latent print cannot confirm identity on its own; it must be combined with the quality of the reference print, the number of matching features, and other case evidence before a firm conclusion is reached.
This model shows the level of evidence and organization needed to complete: A claim-evidence-reasoning paragraph modeling how a forensic examiner argues an identification from comparison to a reference, so students can copy the CER structure and depth without it answering today's histology question.
- 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 one PDF of your Daily Evidence Sheet, Day 14 to your section's D14 · The Fabric Under the Lens assignment in Schoology.
A mechanic studies a tool whose shape allows one job but limits another.
- Which feature makes the tool work?
- What changes if that feature bends or breaks?
- Which observation shows function rather than appearance?
Structure creates possibilities and limits for function.
Living tissues adapt and interact with other systems; a metal tool does not.
- • Tool shape maps to .
- • The job maps to physiological function.
- • Damage maps to a predicted functional change.
Part 4 of 4 · Your work▸
Check your work before submitting
- I can interpret histology against references.
- I can connect anatomy to possible pathology.
4.1 Turn in your work
DueCheck the Schoology assignment for this day- Hand in
- Daily Evidence Sheet, Day 14: the worksheet linked at the top of this page, every Part complete.
How to submit and name your file
Submit one PDF of your Daily Evidence Sheet to Wk5 D14 · The Fabric Under the Lens (PLTW 1.2.4).
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.
Find this lesson's Schoology assignments
These are existing assignments for your section. Follow the directions in the assignment you are working on; this list does not add new work. A PLTW Work row repeats on every day of its lesson; submit it once. Check Schoology for each deadline.
- Wk5 D14 · The Fabric Under the Lens (PLTW 1.2.4)(today's case-day record)
Link will not open? Open Schoology, choose your course and section, and find the title shown above.
- 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. Schoology attaches your name to your upload; on the page itself, write your period and code. Name the file: FirstName LastName - Assignment Title - YYYY-MM-DD.pdf. If you cannot get in, see Mr. Mendoza. Do not skip the work.
How this lesson connects
Keep using what you learned last class: You must record magnification on every microscopy sketch because apparent size means nothing without it, so an unlabeled sketch cannot be trusted or compared by another scientist. Today: A pathologist diagnoses disease by comparing tissue to a normal reference because appearance varies between people, so disease is recognized as deviation from normal rather than from any single slide.
Practice: try a question, then check your answer▸
Claim ceiling for this check: Today's evidence supports a classroom claim about analyze evidence. It cannot prove causation, diagnose a real patient, or justify action outside this room.
Name two things about how a slide is prepared, not the tissue itself, that could make you misread whether a tissue is normal or diseased.
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?▸
Optional practice for this unit's lab skills. Nothing in it is due today. This lesson has more than one, and they cover different skills.
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. Schoology attaches your name to your upload; on the page itself, write your period and code. 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 today's work as this page describes (it is self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
Khan Academy: human body systems (Health and medicine)Sources: slides, readings, and resources▸
Your Unit 1 Take-Home Exam is handed out Friday, October 2. It is due Monday, October 5 at the start of class. Read the study guide first, then take the practice test and check your answers with the key at the end.
The preparation page has the ten-skill checklist, a table of every test we used, the glossary, flashcards, two self-checking practice quizzes and study conversations you can read.
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.
Hand-picked readings and interactives for this lesson, from authoritative open organizations and PLTW's own public course outline.
This week
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