Three neurones, P, Q and R, are connected in sequence. Synapse 1 is between neurones P and Q. Synapse 2 is between neurones Q and R. Neurone R ends at a muscle.
A researcher stimulates neurone P and records the results.
| Location tested | Electrical impulse detected | Neurotransmitter detected in the synaptic gap |
|---|---|---|
| end of neurone P at synapse 1 | yes | yes |
| neurone Q just after synapse 1 | yes | — |
| end of neurone Q at synapse 2 | yes | no |
| neurone R just after synapse 2 | no | — |
Explain the results and predict the response of the muscle.
111 exam-style questions on Edexcel GCSE Biology 2.3 The nervous system and brain, covering 2.3.1 Structures and functions of the brain, 2.3.2 Imaging brain function with scanning, 2.3.3 Limitations in treating nervous system damage, 2.3.4 Neurones and impulse transmission, and 2.3.5 Structure and function of a reflex arc. Each one has a worked solution and a mark scheme showing where the marks go.