Synapses Flashcards
All 6 cards in this deck
What is a synapse?
The junction (small gap) between two neurones.
What is a neurotransmitter?
A chemical released into the synapse that diffuses across the gap and binds to receptors on the next neurone.
What are the steps in transmitting an impulse across a synapse?
e.g. from a sensory neurone to a relay neurone
- The impulse arrives at the end of the sensory neurone and triggers release of neurotransmitter.
- The neurotransmitter diffuses across the gap.
- It binds to receptors on the relay neurone, starting a new electrical impulse.
True or false? The electrical impulse jumps across the gap at a synapse.
False. The impulse cannot cross the gap; a chemical neurotransmitter diffuses across instead.
True or false? A synapse allows impulses to travel in one direction only.
True. Neurotransmitter is released on one side only and receptors are on the other side.
Why does an impulse travel more slowly across a synapse than along an axon?
The neurotransmitter has to diffuse across the gap, which is slower than an electrical impulse.