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The following diagram shows cells involved in detecting and responding to itch stimuli - VCE - SSCE Biology - Question 2 - 2015 - Paper 1
Question 2
The following diagram shows cells involved in detecting and responding to itch stimuli. An example of an itch stimulus is the bite of an insect, which can result in ... show full transcript
Worked Solution & Example Answer:The following diagram shows cells involved in detecting and responding to itch stimuli - VCE - SSCE Biology - Question 2 - 2015 - Paper 1
Step 1
Step 2
Describe how a signal is transferred across the synapse.
Answer
Signal transfer across the synapse involves several key steps:
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Action Potential Arrival: When an electrical impulse (action potential) reaches the presynaptic terminal of the neuron, it triggers the opening of voltage-gated calcium channels.
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Calcium Influx: Calcium ions enter the presynaptic neuron, causing synaptic vesicles filled with neurotransmitter molecules to fuse with the presynaptic membrane.
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Neurotransmitter Release: The fusion of vesicles with the membrane releases neurotransmitters into the synaptic cleft through exocytosis.
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Binding to Receptors: The released neurotransmitters diffuse across the synaptic cleft and bind to specific receptors on the postsynaptic membrane, leading to the generation of a new action potential in the postsynaptic neuron if the signal is strong enough.
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Signal Termination: Finally, neurotransmitters are either broken down by enzymes or reabsorbed by the presynaptic neuron, terminating the signal transmission.