Unit 2.1 Reflexes: Drug impacts on neuron signaling, reflex and reaction time, patient diagnosis challenge.
Your PLTW coursework: Human Body Systems ▸ Unit 2: Research Ready ▸ Lesson 2.1 Getting Nervous ▸ "Activity 2.1.6 Ready, Set, React!", "Project 2.1.8 Lab Leads Challenge (Neurology Diagnosis)"
What to do if absent- 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.
Week overview - Reflexes: reaction time, signaling, and a patient diagnosis challenge
Measure reflexes and , explain how drugs and affect signaling, and use your data in a patient diagnosis challenge.
- 1Run a reaction-time test with a partner and record several trials.
- 2Trace a simple arc from to to to response.
- 3Explain in one sentence how speeds a signal along an axon.
- 4Predict how a drug that slows signaling would change your reaction-time data.
- 5Compare your and reaction-time results to a partner and note any differences.
- 6Use your data and the patient clues to write a short, evidence-based diagnosis.
- • You will be able to measure reflexes and and record clean data.
- • You will be able to trace a arc from to response.
- • You will be able to explain how a drug or changes signaling.
Daily lessons this week
Open any day for its full lesson, the work due that day, and guided notes.
One-paragraph CER taking a position on whether drivers impaired by legal medications should face the same rules as drivers impaired by alcohol.
Labeled -arc diagram (all five components, signal-direction arrows, spinal-cord shortcut marked) plus a two-sentence saltatory-conduction explanation.
Reaction-time with baseline and distraction conditions, all trials with units, condition averages computed, and any outliers flagged with notes.
Bar graph of baseline vs distraction average (labeled, with units) plus a CER explaining how a depressant or stimulant would alter the pattern via synaptic mechanism.
Complete evidence packet: reflex-arc diagram, reaction-time , bar graph, drug-effects CER, and two-sentence reflection on factors that alter reflex speed.
Quick intro to the week
- Hook: your knee-jerk is faster than your conscious thought, because it never has to ask your brain for permission.
- Today's goal: measure reflexes and and use that data to reason like a diagnostician.
- Monday bioethics tie-in: should there be limits on substances that change , like caffeine or medication, before driving or testing?
- Reminder: your graded and reaction data analysis is submitted on the class site.
Your PLTW coursework this week
Do this: Advance the PLTW HBS online benchmark through Unit 2.1 Reflexes.
- • A arc runs from to to to response.
- • speeds signal travel, and some drugs slow or change signaling.
- • Measure reflexes and and record reliable data.
- • Use reaction data and clues to support a patient diagnosis.
📋 PLTW evidence due this week: your and reaction-time data analysis supporting a patient diagnosis.
All PLTW activities are completed inside the PLTW course environment: this page only gives direction.
This week's PLTW tracker
Your week at a glance. Check off each deliverable as you finish it, then submit so Mr. Mendoza can see how the class is pacing.
Use the code Mr. Mendoza gave you, not your name. Saved on this device.
| Day | Date | Focus | Key deliverable |
|---|---|---|---|
| Tuesday | Tue, Mar 16 | Bioethics: drugs and driving | One-paragraph CER taking a position on whether drivers impaired by legal medications should face the same rules as drivers impaired by alcohol. |
| Wednesday | Wed, Mar 17 | Reflex arc and myelin | Labeled reflex-arc diagram (all five components, signal-direction arrows, spinal-cord shortcut marked) plus a two-sentence saltatory-conduction explanation. |
| Thursday | Thu, Mar 18 | Reaction-time lab | Reaction-time data table with baseline and distraction conditions, all trials with units, condition averages computed, and any outliers flagged with notes. |
| Thursday | - | Drug effects on signaling | Bar graph of baseline vs distraction average reaction time (labeled, with units) plus a CER explaining how a depressant or stimulant would alter the pattern via synaptic mechanism. |
| Friday | - | Submit reflex evidence | Complete reflex evidence packet: reflex-arc diagram, reaction-time data table, bar graph, drug-effects CER, and two-sentence reflection on factors that alter reflex speed. |
- M: Philosophy for Kids / John Carroll bioethical debate
- T: teacher background notes + PLTW launch task
- W: lab / data or model work
- Th: analysis / CER or design revision
- F: submit tracker + weekly evidence
Due by week's end: Reflex/reaction data analysis.
5 panels from the illustrated semester.


Fiction. There is no such student. The lessons, labs and dates are the real planned course; the student, the classmates and the conversations are invented.
Lab day: what to bring & watch
This explainer accompanies the PLTW lab protocol: watch it before lab.
What to do when absent
Most days, this class is your PLTW coursework: and PLTW is online and individual. So being out usually just means doing exactly what we did in class, from home.
Open Clever, then myPLTWHow to get there: open Clever and sign in with your Microsoft (district) account. Both myPLTW and Schoology are in Clever. Do the activity in myPLTW. Turn the work in on this site or hand it to Mr. Mendoza, because that is the step that counts as submitted. Schoology only shows your report-card grade later.
You can't do those from home: do this instead: Teacher-posted data/model packet, same objective. Supplemental: Khan: neurons and synapses.
Class still runs. A substitute will post today's plan: complete the online activity above; it's built to be self-guided. Need the concept taught without a teacher? Use this authoritative explainer:
Khan Academy: Neurons and SynapsesVocabulary
Virtual resources
Resources & readings
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).




