Biology A-Level
summation not needed
What summation not needed means in Biology A-Level, as defined for AQA.
Definition of summation not needed
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Reference: AQA
A single action potential arriving is normally enough to make the muscle fibre contract because the motor end plate carries far more receptors, whereas a cholinergic synapse usually needs summation to reach threshold.
Topics that use summation not needed
- Synaptic transmission (A-level only) (AQA A-Level)
Related terms
- acetylcholinesterase inhibition
- agonists and antagonists
- excitatory only at the neuromuscular junction
- Inhibitory synapses and hyperpolarisation
- motor end plate
- postsynaptic receptors
- shared transmission mechanism
- stating the direction of change
Using summation not needed in the exam
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