The nervous system sends fast, short-lived electrical impulses along nerves to one place. The endocrine system releases hormones into the blood: slower, longer-lasting, and they reach every cell but act only on target cells.
A fright makes you jump in a fraction of a second. Your heart is still pounding a few minutes later. Two different systems are at work.
The nervous system is one way the body sends messages. This lesson: the other way, and how they compare.
Engage: Commit to a prediction before you test anything. A wrong guess is fine: it shows you what to look for.
Explore: Try it on the board and compare what happens with your prediction.
Explain: Use the particle model to explain what you saw.
Elaborate: Use the same idea in a new context.
Evaluate: Look back at your first ideas and what changed.
WidthMore contexts, same idea.
Make your prediction first. Help opens once you've locked it in.
EngageCommit to a prediction before you test anything. A wrong guess is fine: it shows you what to look for.
Engage: how do hormones travel?
ExploreTry it on the board and compare what happens with your prediction.
Explore: race them
Press Race and watch both responses to the same fright. Which starts sooner? Which lasts longer?
Try it yourselfYour edits are saved in this browser.
Run the race and compare the nerve with the hormone.
Use the board. This ticks when you get there.
ExplainUse the particle model to explain what you saw.
Explain: comparing the two
In your book: make a comparison table (nerves, hormones) with rows for message, route, speed, duration and where it acts.
Nervous system or endocrine system?
Electrical impulses
Chemical messages in the blood
Very fast
Effects last minutes to years
Goes to one exact place
Reaches the whole body; target cells respond
Elaborate TypicalUse the same idea in a new context.
Elaborate: both at once
A car swerves towards you on your bike. Which part of your response is nervous and which is hormonal?
You brake and steer away
Your heart is still racing five minutes later
Your hands are shaky as you ride home
You flinch
Elaborate WiderUse the same idea in a new context.
Elaborate: insulin
EvaluateLook back at your first ideas and what changed.
Evaluate: look back
Write one sentence: "At first I thought… Now I think… because…"
Revision summary
Nervous system: electrical impulses along neurons; very fast; short-lived; to one exact place.
Endocrine system:hormones released by glands into the blood; slower; longer-lasting; reach every cell but act only on target cells with matching receptors.
Many responses use both.
For teachers
Students compare the nervous and endocrine systems by message, route, speed, duration and target (AC9S9U01, node 4, a hinge node). About 20 minutes.
I can explain that hormones travel in the blood, not along nerves.
I can compare nervous and hormonal responses by speed and duration.
I can explain why only target cells respond to a hormone.
Before class
A concept tutorial for introducing or revising the idea. Set the width with ?width=minimum, typical (default) or wider.
The hinge misconception is that hormones travel along nerves. The Engage question puts it directly.
Board notes: the race is schematic, compressing about 10 minutes into 5 seconds; the curves show shape (sharp spike against slow rise and long tail), not real values.
Running the lesson
Engage: count how many chose 'along a nerve'.
Explore: ask what the long tail of the hormone curve feels like after a fright.
Explain: the target-cell question is the checkpoint.
The hard part (on purpose)
Choosing nerve or hormone by speed, reach and how long the effect lasts. When a student picks one, ask whether it would be quick enough to pull a hand off a hot pan.
When students get stuck
A student thinks adrenaline goes only to the heart. Ask: What carries it? Fix: The blood, which goes everywhere; only cells with receptors respond.
A student says hormones are 'better' because they last longer. Ask: Would a hormone help you pull away from a hot pan? Fix: No: each system suits a different job.
Stretch and support
Stretch: Why would a fault in a hormone receptor have the same effect as having no hormone?
Support: Give the comparison table with rows already labelled.
Where it leads
Next: negative feedback (node 5), using both systems to control body temperature.
What each step is for
Engage: how do hormones travel?: Students who think hormones travel along nerves won't expect the slow rise and long tail; the race shows the difference.
Explore: race them: Seeing the same fright as two curves, one a sharp spike and one a slow rise and long tail, makes speed and duration visible.
Explain: comparing the two: Sorting features into the two systems and linking each to its job is the hinge comparison.
Elaborate: both at once: A real response often uses both systems, each for what it does best.
Elaborate: insulin: A hormone with a clear target links this lesson to blood sugar control in the next.
Now you can
Explain that hormones travel in the blood, not along nerves.
Compare nervous and hormonal responses by speed and duration.
Explain why only target cells respond to a hormone.