Neuron parts and the synapse
Open your materials, follow the steps, then turn in your work.
Label the parts of a neuron and explain how a signal crosses a synapse.
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 dendrite, cell body, axon, and myelin sheath.
Show all 5 required steps
- Read the notes on the dendrite, cell body, axon, and myelin sheath.
- Label a neuron diagram and mark the direction of signal flow.
- Complete the PLTW online task on synaptic transmission.
- Explain in two sentences how neurotransmitters carry the signal across the gap.
- Submit your labeled neuron diagram and synapse explanation.
Lost your place? Interrupted? Step 2 is labeling the neuron and drawing the arrow for signal direction. If your diagram is labeled, move to step 4 and write your two sentences on how neurotransmitters cross the gap.
Check your work before submitting
- You can label the parts of a neuron and the signal direction.
- You can explain transmission across a synapse.
3. Turn in your work
DueCheck Schoology- Hand in
- Labeled neuron diagram (all five parts with signal-direction arrow) and a two-sentence explanation of synaptic transmission.
How to submit and name your file
Submit a photo of your dated notebook 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.
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Check the section number beside Human Anatomy and Physiology in Schoology.
Assignment: Wk8 Lab notebook: Neuron parts and the synapse
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How this lesson connects
Keep using what you learned last class: A rehab plan stages exercises and assistive devices to the affected joint and healing stage so that intensity rises only as tissue can handle it, because loading an unhealed structure causes reinjury that sets recovery back further than going slow. Today: A neuron converts its electrical signal into a chemical one at the axon terminal because electricity cannot cross the synaptic cleft, so neurotransmitters must carry the message to the next cell.
Unit 2 guide: what to keep and use nextOptional: listen or watch a unit review▸
Need help? Warm-up, timing, and directions▸
💡 Big idea: A converts its electrical signal into a chemical one at the axon terminal because electricity cannot cross the synaptic , so neurotransmitters must carry the message to the next cell.
- 0-8Intro: as the functional unit of the nervous system
- 8-25Notes: five parts and synaptic steps
- 25-45PLTW online task: synaptic
- 45-62Label diagram: , soma, axon, , terminal; add signal arrow
- 62-75Write two-sentence explanation: release to binding
- 75-80Submit diagram and explanation; preview Wednesday brain dissection
- • The nervous system is the body's electrical grid. Every sensation, movement, thought, and runs through it.
- • Today we go down to the single cell. A is the functional unit of the nervous system. You need to know every part and which direction the signal travels.
- • The is where electrical becomes chemical. That conversion is the step that most drugs target. Understanding it is essential for the pharmacology content on the WebXam.
- • Your labeled diagram is the artifact. It must show signal direction, all five structural components, and a two-sentence explanation.
- • : dendrites (receive signals), cell body/soma (integrates signals), axon (conducts the action potential), sheath (speeds conduction), axon terminal (releases ).
- • The is the junction between two neurons. Neurotransmitters are released from the presynaptic terminal, cross the synaptic , and bind receptors on the postsynaptic membrane.
- • Many drugs and toxins work by altering release or binding, connecting nervous-system directly to pharmacology and pathophysiology.
PLTW connection and today's work
Complete the neuron-parts task in Activity 2.1.3 The Neuron (Lesson 2.1 Getting Nervous) on myPLTW, then open Activity 2.1.4 The Secret to Signals for the synapse and neurotransmitter-release screens; finish both before the exit check. Work through all screens on dendrites, axon, myelin, and neurotransmitter release.
Today's stopping point: This opens Lesson 2.1. We start with the neuron and reach the brain later this week, the reverse of PLTW's own order, so expect myPLTW to list Mind Matters and Mapping Brain Function before The Neuron. That is expected; today only the neuron task needs to show complete.
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 2.1.3 The Neuron
- Activity 2.1.4 The Secret to Signals
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.
A rehab plan stages exercises and assistive devices to the affected and healing stage so that intensity rises only as can handle it, because loading an unhealed structure causes reinjury that sets recovery back further than going slow.
A converts its electrical signal into a chemical one at the axon terminal because electricity cannot cross the synaptic , so neurotransmitters must carry the message to the next cell.
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 your hand touches a hot stove, exactly what path does that signal take from one to the next before you pull away?
What you already know: A rehab plan stages exercises and assistive devices to the affected and healing stage so that intensity rises only as can handle it, because loading an unhealed structure causes reinjury that sets recovery back further than going slow.
New idea: A converts its electrical signal into a chemical one at the axon terminal because electricity cannot cross the synaptic , so neurotransmitters must carry the message to the next cell.
Visual or model: F1. F1. A lesson illustration or teaching diagram for Neuron parts and the synapse. 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: Structure creates possibilities and limits for function.
- Choose the option the evidence supports and state the limit of the conclusion.
Real biomedical example: When your hand touches a hot stove, exactly what path does that signal take from one to the next before you pull away?
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 nerve cell with branching dendrites that receive input and a long axon that sends an electrical signal to the next cell.
- • : A branching extension of a that receives incoming signals from other nerve cells and carries them toward the cell body.
- • axon: The long, slender fiber of a that carries electrical signals away from the cell body toward other cells.
- • : The junction where a releases chemical messengers across a tiny gap to pass a signal to the next neuron, muscle, or gland.
- • : A chemical messenger released by a that crosses the to pass a signal to the next neuron, muscle, or gland.
- • CNS: The central nervous system, made of the brain and spinal cord, which processes information and directs the body's responses.
- • PNS: The peripheral nervous system: all the nerves outside the brain and spinal cord that carry signals between the body and the central nervous system.
- • : The largest part of the brain, split into two hemispheres, that handles thinking, voluntary movement, sensation, language, and memory.
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.
Nervous-system function emerges from specialized structures that receive, integrate, and transmit signals, while observed behavior reflects multiple pathways and sources of variation.
Limit: A diagram, dissection, test, or reaction-time result cannot isolate every neural process or diagnose a neurological condition.
Structure creates possibilities and limits for function.
Limit: Living tissues adapt and interact with other systems; a metal tool does not.
You can label the parts of a and the signal direction.
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-2027-03-08 · 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 notebook record named on today's page.
- • Change two specific parts and tie each one to a metric like degrees of ROM or pain score.
- • Make the plan shorter and easier so the patient can actually finish every session without quitting.
- • Wait for the patient to actually try the revised plan, since a metric on paper cannot show it worked.
Response: State one choice, cite at least two evidence IDs, explain the rule that connects them, and add one limitation. Submit it as the notebook record.
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 notebook record named on today's page.
Context: A passes information as an electrical signal inside the cell and a chemical signal between cells, which is why anything that changes brain chemistry changes how the message gets through.
- • T1: Read the notes on the , cell body, axon, and sheath.
- • T2: Label a diagram and mark the direction of signal flow.
- • T3: Complete the PLTW online task on synaptic .
- • T4: Explain in two sentences how neurotransmitters carry the signal across the gap.
- • T5: Submit your labeled diagram and explanation.
- • E1: Nervous-system function emerges from specialized structures that receive, integrate, and transmit signals, while observed behavior reflects multiple pathways and sources of variation.
- • E2: Structure creates possibilities and limits for function.
- • E3: You can label the parts of a and the signal direction.
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 parts and the . 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.
Students often think Students often picture neurons as wires that physically touch, so the electrical current flows straight from one into the next.. The trap: That is the trap. Neurons do not touch; there is a synaptic between them. The electrical signal stops at the terminal and is converted to a chemical () that floats across, which is exactly why drugs that change that chemical can change the whole message.
Labeled neuron (signal travels left to right):
- Dendrites: receive incoming signals.
- Cell body (soma): integrates the signals.
- Axon: conducts the action potential away from the cell body.
- Myelin sheath: insulates the axon and speeds conduction.
- Axon terminal: releases neurotransmitter.
Signal-direction arrow: dendrites to cell body to axon to axon terminal.
Synapse explanation (two sentences): When the electrical signal reaches the axon terminal, it triggers the release of neurotransmitter molecules into the synaptic cleft, the tiny gap between the two neurons. The neurotransmitter crosses the gap and binds to receptors on the next neuron's membrane, which converts the chemical message back into an electrical signal in that cell.
This model shows the level of evidence and organization needed to complete: A labeled diagram of a neuron showing all five parts with a signal-direction arrow, plus a two-sentence explanation of how a signal crosses the synapse from one neuron to the next.
- Date and label the entry.
- Record the procedure, observation, or design decision clearly.
- End with what the evidence means and the next step.
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 a photo of your dated notebook page.
- 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 Neuron parts and the synapse. 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.
Play the cold open at the start of the unit to set the scene. Each recording is AI-generated and simulated (fictional callers, no real people or student data).
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 2: Research Ready. 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 2 notebook: Research Ready 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.
This site may ask you to verify you are human. If it blocks you on a school device, ask for the class copy.
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.
Trace one signal in order: it starts at the dendrite. Name the next three structures it passes through to reach the next neuron.
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.
The bench work needs equipment you do not have at home. Do the thinking half now: read the procedure, write your prediction, and set up your data table so it is ready.
Back in class. Ask Mr. Mendoza for the class data set, or for a bench slot to run it yourself. Do not submit a Notebook check with invented numbers.
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: Nervous System- 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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