Physiology variables
Open your materials, follow the steps, then turn in your work.
Launch Problem 2 by identifying variables for a human physiology research design.
1. Open your materials
Use the materials named in the first step below. Open lesson resources.
2. Start the work
Read the Problem 2 physiology overview.
Show all 5 required steps
- Read the Problem 2 physiology overview.
- Choose a physiological measure to investigate, such as heart rate.
- Identify the independent, dependent, and controlled variables.
- Write a testable hypothesis about your measure.
- Submit your variables and hypothesis.
Lost your place? Lost your place? Check whether you have chosen a physiological measure and written your three variables. If yes, move to writing your testable hypothesis; if not, start by reading the Problem 2 overview and picking a measure such as heart rate.
Check your work before submitting
- You can name independent, dependent, and controlled variables.
- You can write a testable physiology hypothesis.
3. Turn in your work
DueCheck Schoology- Hand in
- Problem 2 launch: chosen physiological measure, identified independent/dependent/controlled variables, and a testable hypothesis.
How to submit and name your file
Use the submission route shown on today's today's page.
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.
How this lesson connects
Keep using what you learned last class: You must answer questions from your own evidence so that the panel trusts your design is real, because a confident guess that proves wrong destroys credibility instantly. Today: You must define your variables and a testable hypothesis first so that your measurements mean something, because an undefined study cannot tell you what actually caused a change.
Optional: listen or watch a unit review▸
Need help? Warm-up, timing, and directions▸
💡 Big idea: You must define your variables and a testable hypothesis first so that your measurements mean something, because an undefined study cannot tell you what actually caused a change.
- 0-10Introduce Problem 2: physiology investigation overview and evidence expectations
- 10-25Read the Problem 2 physiology overview and discuss physiological measures worth studying
- 25-40Choose a measure and identify independent, dependent, and controlled variables
- 40-60Write a testable hypothesis linking the to the dependent measure
- 60-75Submit your variables and hypothesis
- 75-80Pair-check: does your partner's hypothesis have all three variable types? Give one piece of feedback.
- • Problem 1 is complete. Problem 2 asks you to investigate human physiology using real data.
- • Today you launch Problem 2 by choosing a physiological measure and designing a testable hypothesis around it.
- • Getting the variables right now prevents weeks of wasted data collection later.
- • Molecular and Genetic Technology and Microbiology Testing on WebXam 072125 both require experimental design fluency.
- • The definitions of independent, dependent, and controlled variables and how to apply them to a physiology investigation.
- • What makes a hypothesis testable rather than merely a guess.
- • Why choosing a measurable physiological variable -- such as heart rate -- is the first constraint that shapes the entire study design.
PLTW connection and today's work
Open Problem 2 Exploring Human Physiology in your myPLTW course shell and locate the variable-identification and hypothesis activity.
Today's stopping point: Problem 1 is fully closed out; today you launch Problem 2 by identifying variables and writing your first physiology hypothesis.
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 2.1.1 Scientific Research
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.
You must answer questions from your own evidence so that the panel trusts your design is real, because a confident guess that proves wrong destroys credibility instantly.
You must define your variables and a testable hypothesis first so that your measurements mean something, because an undefined study cannot tell you what actually caused a change.
A research team lays out its question, variables, controls, sampling plan, measurement record, and analysis before deciding what the data support.
- Which variable is changed or compared?
- Which conditions and measurements must stay consistent?
- Which conclusion is inside the study's evidence boundary?
Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
A well-organized classroom study can still be limited by , measurement quality, confounding, and the population represented.
- • Question and variable cards map to the study design.
- • Control and measurement cards map to fair, reproducible data collection.
- • The conclusion card maps to a bounded claim supported by the analysis.
Driving question: If you want to study how something affects heart rate, exactly which variable do you change, which do you measure, and which do you have to keep constant?
What you already know: You must answer questions from your own evidence so that the panel trusts your design is real, because a confident guess that proves wrong destroys credibility instantly.
New idea: You must define your variables and a testable hypothesis first so that your measurements mean something, because an undefined study cannot tell you what actually caused a change.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Physiology variables. Use it with E1-E3; it is a model or context image, not experimental or patient data. What to notice: Trace the labeled system, test, or design relationship and identify which evidence should trigger revision.
- Observe or measure the relevant feature in physiology variables.
- Organize the observation with a stable evidence ID.
- Apply this rule: Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: If you want to study how something affects heart rate, exactly which variable do you change, which do you measure, and which do you have to keep constant?
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.
- • hypothesis: A testable, falsifiable prediction about how variables relate, written so an experiment can support it or prove it wrong.
- • : The one factor a researcher deliberately changes in an experiment to test its effect on the measured outcome.
- • : The outcome a researcher measures in an experiment, which may change in response to the variable being tested.
- • control: The comparison condition that isolates the effect of the variable being tested by keeping everything else the same.
- • : The number of subjects or observations in a study; larger samples give more reliable results and reduce the role of chance.
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.
A planned study connects its question to defined variables, controls, sampling, measurement, and analysis so the resulting data can support a bounded and reproducible conclusion.
Limit: A statistical difference or trend does not automatically establish practical importance, causation, generalizability, or freedom from bias.
Define variables, controls, sampling, units, and the analysis plan before interpreting a result; analysis cannot repair biased or inconsistent measurement.
Limit: A well-organized classroom study can still be limited by , measurement quality, confounding, and the population represented.
You can name independent, dependent, and controlled variables.
Limit: E3 defines the classroom product or success criterion. It is not independent scientific evidence and cannot justify a clinical or causal claim.
PLTW-BFH-2027-02-26 · Simulated classroom evidence scenario
Your role: biomedical design team member
Decision: Your team must decide what the evidence from physiology variables supports before submitting the exit response named on today's page.
- • Name exercise as the variable you change, heart rate as the measurement, and list your controls.
- • Call heart rate the , since it is the number your sensor actually collects during the trial.
- • Hold the hypothesis until you decide which conditions must stay constant, since undefined controls make the numbers unreadable.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the exit response.
Claim ceiling: Today's evidence supports a classroom claim about physiology variables. It cannot prove causation, diagnose a real patient, or justify action outside this room.
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.
- • The solution must address the stated need in physiology variables.
- • 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 often think the is whatever they measure with an instrument, so they call heart rate the independent variable because that is the number they collect.. The trap: That is a trap because heart rate is the ; it responds. The is the thing you deliberately change, such as exercise or music, and mixing them up means your whole study answers the wrong question.
Problem 2 launch: variables and hypothesis
Physiological measure I will investigate: heart rate.
Variables:
- Independent (what I change): exercise level, sitting at rest versus 2 minutes of step-ups.
- Dependent (what I measure): heart rate in beats per minute.
- Controlled (what I keep the same): same person, same time of day, same step height and pace, 1-minute rest before each reading.
Testable hypothesis: If a person does 2 minutes of step-ups, then their heart rate will increase compared to their resting rate, because exercise raises the body's demand for oxygen and the heart pumps faster to meet it.
Why this is testable: it predicts a measurable change (heart rate) tied to a variable I control (exercise level), so I can confirm or disconfirm it with data.
This model shows the level of evidence and organization needed to complete: A Problem 2 launch ticket naming a physiological measure, its independent, dependent, and controlled variables, and a testable hypothesis.
- Name the prompt or task.
- Answer it directly with the key evidence.
- Check that the response matches the requested format.
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 your variables and hypothesis on Schoology by end of period.
- 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 Physiology variables. 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 Clever, then Schoology, and find each one by the name shown on its card.
Use this if you were absent, got stuck, or need another pass before you submit the lesson artifact.
Placement rationale
Matched ER presentation and physiology bridge by path:Biomedical-Innovations/Problem-1_Emergency-Room/1.1_Emergency-Room; keywords:emergency room, clinical. Score 142. 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 ER presentation and physiology bridge by path:Biomedical-Innovations/Problem-2_Human-Physiology/2.1_Human-Physiology; keywords:physiology. Score 134. 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 ER presentation and physiology bridge by path:Biomedical-Innovations/Problem-2_Human-Physiology/2.1_Human-Physiology; keywords:physiology. Score 134. Visibility: student-schoology (student-facing resource; link through Schoology rather than local path).
Sign in to Clever with your district Microsoft account to open Schoology or myPLTW. Follow today's posted steps. If myPLTW will not open, use the posted alternative and tell Mr. Mendoza. Turn in your completed work through the Schoology assignment.
Practice: try a question, then check your answer▸
Claim ceiling for this check: Today's evidence supports a classroom claim about physiology variables. It cannot prove causation, diagnose a real patient, or justify action outside this room.
You test whether caffeine raises heart rate. Which is the independent variable and which is the dependent variable?
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.
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 Exit ticket.
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:
Khan Academy Scientific Method- 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.
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