Coordination and Response: Question 7
Syllabus 14.1
Which of the following is an example of a reflex action rather than a voluntary action?
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Worked solution
Step 1: Distinguish voluntary from reflex actions
A voluntary action is one that a person consciously decides to carry out; it involves the brain making a decision, and can take a variable amount of time depending on the choice being made.
A reflex action is a rapid, automatic response to a stimulus that does not involve conscious thought or decision-making. Many reflex actions are coordinated by the spinal cord alone, allowing them to happen very quickly and protect the body from harm.
Step 2: Apply this to each option
- A: raising a hand to answer a question is a conscious decision, a voluntary action.
- B: blinking as an object suddenly approaches the eye happens automatically, without the driver deciding to do it, to protect the eye from injury, a reflex action.
- C: choosing which teammate to pass to involves conscious judgement about the game, a voluntary action.
- D: selecting which keys to press requires conscious thought about the music, a voluntary action.
Why the other options are wrong
- A, C and D all involve a conscious decision being made based on the situation, even though some of these decisions may be made quickly. This conscious element makes them voluntary, not reflex, actions.
Final answer
- The blink in response to the approaching insect happens automatically, without conscious thought, so it is the reflex action, option B.