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Question
What are the causes of ‘Myopia’?
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Solution
Myopia, also known as short-sightedness, occurs due to the lengthening of the eyeball. With this defect, nearby objects can be seen clearly but distant objects cannot be seen clearly.
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Millions of people in the developing countries of the world are suffering from corneal blindness. These persons can be cured by replacing the defective cornea with the cornea of a donated eye. A charitable society of your city has organised a campaign in your neighbourhood in order to create awareness about this fact. If you are asked to participate in this mission, how would you contribute in this noble cause?
(i) State the objective of organising such campaigns.
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The photosensitive pigment present in the rods of the retina.
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Name the parts labeled 1 to 4.
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Assertion: Myopia is the defect of vision in which a person cannot see distant objects clearly.
Reason: This due to eye-ball being too short.
Complete the following table by observing the given figures:
| Figure → |  |
 |
| Points ↓ | ||
| (a) Name of the defect | ______ | ______ |
| (b) Position of the image | ______ | ______ |
| (c) Lens used to correct the defect | ______ | ______ |
