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प्रश्न
Write down the following activities in the correct order for a simple reflex arc:
(a) impulse travels in the motor fibre
(b) impulse travels in the sensory fibre
(c) effector organ stimulated
(d) impulse crosses the synapse
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उत्तर
The pathway taken by nerve impulses in a reflex action is called a reflex arc. It is an automatic response to a stimulus. When a stimulus is given to a receptor, the receptors produce an impulse in the sensory fibre. The sensory fibre carries this message in the form of an electrical stimulus across the synapse. From the synapse, the impulse travels in the motor fibre and stimulates the effector organ to produce the desired response.
The correct order for a simple reflex arc is:
(b) →(d) → (a) → (c).
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संबंधित प्रश्न
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2) Give the technical term for the point of contact between the two nerve cells.
3) Name the parts numbered 1, 2 and 3.
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