Which reflex is controlled by the brain stem?
Answer and explanation
Correct answer: B. The change in the size of the pupil
The pupil reflex is controlled in the brain, while the knee-jerk and withdrawal reflexes go through the spinal cord.
Answer: The change in the size of the pupil.
Why not the others: The knee-jerk: it is a spinal reflex. Withdrawal of a hand from a hot object: it is a spinal reflex. Writing with a pen: it is a voluntary action.
Answer: The change in the size of the pupil.
Why not the others: The knee-jerk: it is a spinal reflex. Withdrawal of a hand from a hot object: it is a spinal reflex. Writing with a pen: it is a voluntary action.
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