In a reflex action in which a person touches a hot plate and pulls their arm away, neurons of different lengths are involved. Which answer identifies the relative lengths of the neurons?

Answer:

9) F

Sensory neurones are the longest since they have to cover the length from the point of stimulus to the spinal chord.

Motor neurones are shorter than sensory neurones but longer than relay neurones since they have to travel from the spinal cord to the muscle erector.

Relay neurones are the shortest as they are only in the spinal cord.