Synapses: How Neurones Communicate
Part of Nervous System — GCSE Biology
This deep dive covers Synapses: How Neurones Communicate within Nervous System for GCSE Biology. Topic 2: Nervous System It is section 4 of 17 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 4 of 17
Practice
15 questions
Recall
20 flashcards
🔗 Synapses: How Neurones Communicate
Synapses are tiny gaps (about 20 nanometres wide) between two neurones. Electrical impulses cannot jump across this gap — instead, chemical messengers called neurotransmitters carry the signal across.
How a synapse works (4 steps):
- An electrical impulse arrives at the end of the first neurone (pre-synaptic neurone).
- This triggers the release of neurotransmitters from tiny vesicles into the synaptic cleft.
- The neurotransmitters diffuse across the gap and bind to specific receptor proteins on the next neurone.
- This binding triggers a new electrical impulse in the second neurone (post-synaptic neurone).
Why synapses matter: Synapses ensure signals travel in one direction only (neurotransmitters are only released from the pre-synaptic side). They also allow signals to be amplified, inhibited, or combined from multiple neurones — this is how the brain processes complex information.