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When we touch a cactus unknowingly,we ge...

When we touch a cactus unknowingly,we get pricked by the throns.We withdraw our hands immediately.Which type of neuron gets activated first.

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(i)When we are pricked by a cactus,the sensory neurons are activated immediately.
(ii)They take the massage to the brain or spinal cord.
(iii)The massage given by the brain or spinal cord is brought back by the motor neuron.
(iv)The motor meuron carries the massage to the hand muscles .We immediately pull our hand away from the cactus.
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