AQA GCSE · Question 02.2.2 · Homeostasis and Response
Which part of the nerve pathway is labelled B?
Answer options:
A.
Motor neurone
B.
Receptor
C.
Relay neurone
D.
Spinal cord
How to approach this question
Trace the path of the nerve impulse. It travels from the receptor (A) to the spinal cord (C). From the spinal cord, an impulse is sent to the muscle to cause a response. The neurone that carries this impulse to the muscle is labelled B. Identify the name for this type of neurone.
Full Answer
A.Motor neurone✓ Correct
Motor neurone
The reflex arc pathway is: Stimulus → Receptor → Sensory Neurone → Relay Neurone (in CNS) → Motor Neurone → Effector → Response. Part B is the neurone that carries the impulse away from the central nervous system (C) to the effector (the muscle). This is the motor neurone.
Common mistakes
✗ Confusing the motor neurone with the sensory neurone (which carries the impulse towards the CNS).
✗ Thinking B is the muscle itself; B is the nerve cell leading to the muscle.
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