Tissue and heart lab
Open your materials, follow the steps, then turn in your work.
Examine histology slides under the microscope and observe gross heart anatomy following an SOP.
1. Open your materials
Before the lab: Complete Sheep Heart Dissection simulation.
2. Start the work
Read the microscopy SOP and set magnification and focus correctly.
Show all 5 required steps
- Read the microscopy SOP and set magnification and focus correctly.
- Identify epithelial, connective, muscle, and nervous tissue on slides.
- Sketch each tissue with magnification and one identifying feature labeled.
- Examine a preserved heart and locate chambers, valves, and vessels.
- Record one limitation of slide-based identification and one error source.
Lost your place? Lost your place? This is the microscopy and heart lab. Check the SOP and your magnification/focus (step 1), make sure each of your four tissue sketches has magnification and one labeled feature (steps 2-3), then examine the preserved heart for chambers and valves (step 4).
Check your work before submitting
- I can identify the four tissue types under magnification.
- I can locate the major structures of the heart.
Before lab work: read the safety rules
- Preserved specimens contain fixative chemicals (formaldehyde or formalin substitute): wear nitrile gloves and goggles at all times at the heart station; work in a well-ventilated area.
- Do not inhale deeply over an open specimen container; if you feel lightheaded or notice strong fume odor, move away and notify the teacher.
- Histology slides are glass: handle by the edges only; place cracked or broken slides in the designated sharps container immediately.
- Never touch the microscope lens with anything other than lens paper; do not use paper towels or your clothing to clean optics.
- After the heart examination, seal the specimen tray, remove gloves using the glove-to-glove technique, and wash hands with soap and water for at least 20 seconds.
- Dispose of all gloves, paper towels, and disposable materials used at the heart station in the labeled biological-waste bag, not the regular trash.
3. Turn in your work
DueCheck Schoology- Hand in
- Lab notebook pages: four histology sketches (one per tissue type, magnification labeled, one feature identified), a labeled heart diagram with chambers, valves, and major vessels, and one limitation and one error source noted.
How to submit and name your file
Photograph your notebook pages and upload to the tracker before leaving class.
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. Check Schoology for each deadline.
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How this lesson connects
Keep using what you learned last class: A pathologist studies just four tissue types instead of dozens of organs because every organ is built from those four, so learning how each tissue breaks lets you read damage anywhere in the body. Today: 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.
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 run the autopsy stations: document findings on the body diagram, read the organ findings, and put your hands (virtually) on the heart's real anatomy.
Remember: A wound that bled tells you the person was alive when it happened. Vital response is the body time-stamping its own injuries.
- Activity 1.2.4 Histology
- Activity 1.2.5 Gross Anatomy Examination
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 015 · Insulin pen recovered from desk drawer · Chemistry 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 13 pack (paper in class; the PDF is above and on the Schoology assignment)
- Investigative Notebook: Body diagram, front and back
- Investigative Notebook: Logic tree pruning notes
- Investigative Notebook: Day 13 Cornell page
Lab notebook pages: four histology sketches (one per tissue type, magnification labeled, one feature identified), a labeled heart diagram with chambers, valves, and major vessels, and one limitation and one error source noted.
Photograph your notebook pages and upload to the tracker before leaving class.
Schoology assignment: Wk5 D13 · Autopsy Day (PLTW 1.2.4)
Before the hands-on lab
- Sheep Heart Dissection 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▸
Need help? Warm-up, timing, and directions▸
💡 Big idea: 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.
- 0:00Review SOP for microscopy and heart examination; PPE check before anyone opens containers
- 0:10Microscopy station: four prepared slides; identify and sketch each at 40x and 100x
- 0:40 station: examine preserved heart; locate and label four chambers, four valves, major vessels
- 1:00Record one limitation of slide-based identification and one error source in lab notebook
- 1:05Station cleanup per SOP: cover specimens, return slides to tray, clean microscope stage
- 1:10Preview Thursday analysis; brief debrief on what surprised students
- • Today is the first major hands-on lab of this unit. You are going to look at real under a real microscope and examine a preserved heart.
- • Before you touch the microscope: read the SOP. Set your stage at the lowest magnification first, focus, then increase. Skipping this step cracks slides.
- • The preserved heart is in fixative. The fixative keeps it from decomposing, but it is a chemical and you will wear gloves and work in a ventilated area. The smell is formaldehyde or a formalin substitute. Do not put your face near the container.
- • You are scientists today. Every sketch goes in the notebook with magnification labeled. Every heart structure you identify gets labeled on a diagram. This is your evidence.
- • Magnification must always be recorded with a microscopy sketch because the apparent size of a structure is meaningless without it.
- • The heart has four chambers (right/left atria and ventricles), four valves (tricuspid, pulmonary, mitral, aortic), and its wall is primarily cardiac muscle .
- • Preserved specimens have altered texture, color, and smell compared to fresh ; fixative chemicals require PPE and ventilation.
PLTW connection and today's work
In myPLTW, open Lesson 1.2 Master the Morgue and go to Activity 1.2.4 Histology and Activity 1.2.5 Gross Anatomy Examination. Record your slide observations in the first one and your heart-anatomy labels in the second.
Today's stopping point: You took notes on tissue types Tuesday. Today all four tissue sketches and the heart-anatomy diagram should be in your notebook before cleanup.
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
- Activity 1.2.4 Histology
- Activity 1.2.5 Gross Anatomy Examination
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
Finish the assigned lab safely before starting extra practice.
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.
A pathologist studies just four types instead of dozens of organs because every organ is built from those four, so learning how each tissue breaks lets you read damage anywhere in the body.
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 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.
Driving question: When you sketch a slide at 400x and then hold a preserved heart, what can you actually observe that would help explain how this person died?
What you already know: A pathologist studies just four types instead of dozens of organs because every organ is built from those four, so learning how each tissue breaks lets you read damage anywhere in the body.
New idea: 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.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Tissue and heart lab. Use it with E1-E3; it is a model or context image, not experimental or patient data. What to notice: Trace the labeled observation or evidence sequence before choosing an explanation.
- Observe or measure the relevant feature in today's lesson.
- 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: When you sketch a slide at 400x and then hold a preserved heart, what can you actually observe that would help explain how this person died?
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.
- • : 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.
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 identify the four types under magnification.
Limit: E3 defines the classroom product or success criterion. It is not independent scientific evidence and cannot justify a clinical or causal claim.
PLTW-PBT-2026-09-28 · Simulated classroom evidence scenario
Your role: biomedical investigator
Decision: Your team must decide what the evidence from today's lesson supports before submitting the lab report named on today's page.
- • Name the deviation by holding my sketch against the healthy reference image, since disease shows up as a difference from normal.
- • 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.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the lab report.
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 lab report named on today's page.
Context: links the microscopic and the visible, so a slide and a whole heart together give a pathologist the evidence one alone cannot.
- • T1: Read the microscopy SOP and set magnification and focus correctly.
- • T2: Identify , , muscle, and nervous on slides.
- • T3: Sketch each with magnification and one identifying feature labeled.
- • T4: Examine a preserved heart and locate chambers, valves, and vessels.
- • T5: Record one limitation of slide-based identification and one error source.
- • 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 identify the four types under magnification.
Measurements: No patient measurement is supplied unless it appears explicitly in E1-E3 or F1. Do not invent a value.
Figure finding: Teaching diagram for and heart lab. Trace the labeled observation or evidence sequence before choosing an explanation. 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.
- • The solution must address the stated need in today's lesson.
- • The decision must be supported by E1-E3.
- • The final product must make the success criteria visible.
- • Complete the work inside the 80-minute block.
- • Use only supplied or teacher-approved materials and evidence.
- • Do not trade , accessibility, or privacy for speed.
- • and evidence quality: must pass before scoring other criteria.
- • User need and effectiveness: highest scored criterion.
- • Time, cost, and ease of use: compare only after and effectiveness pass.
Test evidence: For each option, record the E1-E3 result that supports or fails each criterion. Do not assign a score without a named observation.
- Version or option tested
- Criterion met or missed
- Evidence ID and result
- Revision made
- Reason for the revision
- Need and user
- Criteria and constraints
- Chosen option and evidence
- Test result
- Revision and reason
Students often think Students think a microscopy sketch stands on its own, so writing the magnification is just an optional formality the teacher wants.. The trap: That is a trap because apparent size is meaningless without magnification; the same structure looks ten times bigger at 400x than 40x, so a sketch without magnification cannot be interpreted or compared by anyone else.
Histology sketches (Andre, Period 4):
- Epithelial at 100x: tightly packed cells, labeled.
- Connective at 100x: scattered cells in a matrix, labeled.
- Muscle at 100x: long striated fibers, labeled.
- Nervous at 100x: branching cell with extensions, labeled.
Heart diagram: labeled right and left atria, right and left ventricles, tricuspid and mitral valves, aorta and pulmonary artery.
Limitation: A thick slide section overlapped cells, making one tissue hard to identify. Error source: focusing at the wrong magnification could make a structure look larger than it is, so I recorded magnification on each sketch.
| Structure | Type |
|---|---|
| Right and left atria | Chambers |
| Right and left ventricles | Chambers |
| Tricuspid and mitral | Valves |
| Aorta and pulmonary artery | Major vessels |
This model shows the level of evidence and organization needed to complete: Notebook pages with four histology sketches (magnification and one feature labeled) and a labeled heart diagram with chambers, valves, and major vessels, plus a limitation and error source.
- State the question and method.
- Present the observations and data with units.
- Explain the result, limitations, and next investigation.
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: Photograph your notebook pages and upload to the tracker before leaving 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 Tissue and heart lab. 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 and interactives for this lesson, from authoritative open organizations and PLTW's own public course outline.
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.
How many chambers and how many valves does the heart have, and which tissue type makes up most of its wall?
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?▸
Run this before you touch the bench. It is built from the real lab procedure, so the decisions you make here are the ones you will make with the equipment in your hands. This lesson has more than one, and they cover different skills.
I can name the procedure's purpose and the evidence I will record. I can name today's hazards and the control for each: Preserved specimens contain fixative chemicals (formaldehyde or formalin substitute): wear nitrile gloves and goggles at all times at the heart station; work in a well-ventilated area. My data table is ready before materials are handled.
Finish the checklist before you handle any material.
- • Preserved specimens contain fixative chemicals (formaldehyde or formalin substitute): wear nitrile gloves and goggles at all times at the heart station; work in a well-ventilated area.
- • Do not inhale deeply over an open specimen container; if you feel lightheaded or notice strong fume odor, move away and notify the teacher.
- • Histology slides are glass: handle by the edges only; place cracked or broken slides in the designated sharps container immediately.
- • Never touch the microscope lens with anything other than lens paper; do not use paper towels or your clothing to clean optics.
- • After the heart examination, seal the specimen tray, remove gloves using the glove-to-glove technique, and wash hands with soap and water for at least 20 seconds.
- • Dispose of all gloves, paper towels, and disposable materials used at the heart station in the labeled biological-waste bag, not the regular trash.
- 1Before materials are handled, identify the purpose, variables or comparison, controls, measurement units, and stop-work condition.
- 2Read the microscopy SOP and set magnification and focus correctly.
- 3Identify epithelial, connective, muscle, and nervous tissue on slides.
- 4Sketch each tissue with magnification and one identifying feature labeled.
- 5Examine a preserved heart and locate chambers, valves, and vessels.
- 6Record one limitation of slide-based identification and one error source.
- 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.
Use the virtual and heart- resources to identify all four types and label heart structures, submitting sketches with magnification noted.
learn.genetics Inside a CellPhotograph your notebook pages and upload to the tracker before leaving class.
Class still runs. Complete the online activity above (it's self-guided). Need the concept taught without a teacher? Use this authoritative explainer:
Khan Academy: human body systems (Health and medicine)- 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.
- 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.
This week
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