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प्रश्न
Define the following:
Reflex action
Define the following term:
Reflex action
Define reflex action.
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उत्तर
Reflex action is an automatic/quick/immediate, involuntary action in the body brought about by a stimulus. This mechanism prevents injury to the body by triggering a rapid and automatic response.
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संबंधित प्रश्न
With the help of a neat and labelled diagram, describe reflex arc.
Fill in the following blanks with suitable words :
Our.............system allows us to react to our surroundings. Information from receptors passes along...........neurons to our brain. Our brain sends impulses along..........neurons to our muscles.
Name the function of cerebrum.
What is a reflex action? Explain with the help of an example.
A cell (or group of cells) in a sense organ which is sensitive to a particular type of stimulus is called :
(a) interceptor
(b) effector
(c) receptor
(d) acceptor
Which of the following is not an involuntary action?
(a) vomiting
(b) chewing
(c) heart beat
(d) salivation
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.
Your are driving your bicycle at a fast speed. Suddenly, a small boy comes in front of your cycle and, without wasting any time in thinking, you immediately apply the brakes and accident is avoided. What name is given to such an action?
Differentiate between natural reflex and conditioned reflex. Give examples to illustrate your answer.
Complete the following statement by choosing the correct alternative from the choice given in bracker:
Reflex action is controlled by
(i) brain (ii) spinal cord
(iii) autonomic (iii) peripheral nervous system
State whether the following is simple reflex, conditioned reflex or neither of the two:
Blushing: ……………….
What is the difference between reflex action and voluntary action?
List in tabular form two differences between reflex action and walking.
State whether the following is
Constriction of pupil
State whether the following is simple reflex, conditioned reflex or neither of the two.
Lifting up a book
Complete the following sentence with appropriate Word
Which of the following is not a natural reflex action?
In reflex action, the reflex arc is formed by ______
Reflex actions are mediated through ____________.
Categorise the following under stimulus and response.
Seeing a green light turning into red at a road crossing before applying the brakes.
Categorise the following under stimulus and response.
Pain in the eye if something falls into it.
