MDCAT · CHAPTER 5
Coordination & Control
Follow ions and channels across an axon membrane, then see how an electrical signal becomes chemical at a synapse.
Your study notes
01 / LESSON
Build the explanation.
- Explain how ion gradients create the resting membrane potential.
- Trace depolarisation, repolarisation and the refractory period.
- Describe chemical synaptic transmission and one-way signalling.
02 / NOTES
The essentials, in one place.
- Resting potential depends on ion gradients and selective permeability.
- Voltage-gated sodium entry causes depolarisation; potassium exit restores negativity.
- Refractory periods support one-way propagation.
- Calcium entry links an arriving impulse with neurotransmitter release.
03 / ACTIVITY
Test the idea by changing something.
Predict the result first, run the activity, then explain what changed and why.
04 / DIAGRAM
Make the connections visible.
Ion gradients and leak permeability maintain negativity.
Sufficient depolarisation opens Na⁺ channels.
Rapid Na⁺ entry makes the inside positive.
Na⁺ channels inactivate and K⁺ leaves.
Channels reset before normal excitability returns.
Cover the labels, redraw the sequence or comparison, and explain each connection aloud.
See diagrams in the full explanation ↗05 / QUIZ
Retrieve before you reread.
Build a timed test from this chapter’s 100 practice questions. Questions and options are shuffled; missed answers feed your revision notebook.
Original practice items, including related concept variants; not official examination questions.06 / REVISION SHEET
Take the chapter away with you.
A print-friendly sheet brings together the learning targets, key points, concept diagram, written recall prompts and applied MCQs. Add the answer key when you are ready to check.
Print / save the chapter sheet ↗