An impulse crosses a synapse from a relay neurone to a motor neurone. Two electrodes record the time from the impulse reaching the end of the relay neurone until it reaches each position along the motor neurone.
The recorded time includes the delay at the synapse. This synaptic delay is the same for both electrodes.
| Distance along the motor neurone / m | Recorded time / ms |
|---|---|
| 0.16 | 4.0 |
| 0.64 | 10.0 |
Calculate the speed of the impulse along the motor neurone.
Show your working.
A third electrode is placed 0.88 m along the motor neurone.
Calculate the expected recorded time for the impulse to reach this electrode.
Show your working.
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.