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प्रश्न
What will you do if someone pricks your hand with a needle? Elucidate the pathway of response with a neat labelled diagram.
उत्तर
Reflex action and its pathway
The pathway taken by nerve impulses to accomplish reflex action is called the reflex arc.
- When the hand is pricked by a needle, the stimulus is the prick (touch) pain, which is sensed by a receptor called touch or pain receptors in the skin in our hand. This stimulus in tum triggers an impulse in a sensory neuron.
- The sensory neuron transmits or conveys the message to the spinal cord.
- The spinal cord interprets the stimulus and the impulse is passed on to the relay neuron, which in tum transmits it to a motor neuron.
- Motor neurons carry commands from the spinal cord to our arms.
- The muscle in our arm contracts and we withdraw our hand immediately from the needle prick. The muscle is the effector organ that has responded to the prick (pain).
APPEARS IN
संबंधित प्रश्न
Which part of the brain maintains posture and equilibrium of the body?
Give examples of unconditional reflexes
Name the most important part of the human brain.
Define reflex arc. Give the flow chart of a spinal reflex arc.
When we touch a hot plate unknowingly, then this heat is sensed by a receptor P present in our fingers. The receptor triggers and impulse in neuron Q which transmits the message to an organ R which is a part of the central nervous system. Here the impulse is passed on to a neuron S which in turn passes it to a yet another neuron T. The neuron T passes the impulse to a tissue U in our arm. The tissue U then contracts and pulls our hand away from the hot plate.
(a) What is the name of (i) receptor P (ii) neuron Q, and (iii) organ R?
(b) What is (i) neuron S, and (ii) neuron T?
(c) Name the tissue U.
(d) What name is given to the phenomenon in which hand is pulled away quickly from the hot plate?
(e) Name the effector in this whole process.
Note the relationship between the first two words and suggest the suitable word/words for the fourth place.
Receptor : Sensory nerve :: Motor nerve : ______.
what do we refer to in the nervous system when we say:
Natural and conditioned …………………
State whether the following is simple reflex, conditioned reflex or neither of the two.
Contraction of eye pupil
Mention, if the following statement is True or False
Reflex action involves brain
Mention, if the following statement is True or False
Reflex action is a unit of nervous action
