Define reflex action. With the help of a flow chart show the path of a reflex action such as sneezing.
Generated by claude-sonnet-4-6 · 2026-06-15 06:50 · grounding rag
Model Answer
Reflex action: It is a spontaneous, automatic and immediate response to a stimulus that does not involve thinking. It is controlled by the spinal cord through a reflex arc.
Path of reflex action (sneezing):
$$\text{Stimulus (irritant in nose)} \rightarrow \text{Receptor (sensory cells in nose)} \rightarrow \text{Sensory nerve} \rightarrow \text{Spinal cord (reflex arc)} \rightarrow \text{Motor nerve} \rightarrow \text{Effector (muscles)} \rightarrow \text{Response (sneeze)}$$
Source: Chapter 6, Section 6.1.1 — What happens in Reflex Actions?
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Explanation
- Definition fetches 1 mark: include key words — sudden/automatic, without thinking, response to stimulus.
- Flow chart fetches 2 marks: must show all five steps — stimulus → receptor → sensory nerve → spinal cord → motor nerve → effector → response. Missing any node loses a mark.
- Examiners accept a linear arrow diagram (as above) or a box-and-arrow chart; both are valid.
- The role of the spinal cord (not the brain) in completing the arc is essential to mention.