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प्रश्न
In what two whys is a yellow spot different from the blind spot?
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उत्तर
The yellow spot has more cones and less rod cells. The blind spot has no photosensitive cells.
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संबंधित प्रश्न
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Name the body part with which the terms myopia and hypermetropia are connected.
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Name the type of defect he is suffering from.
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Observer the following diagram and answer the questions.
a) Which eye defect is shown in this diagram?
b) What are the possible reasons for this eye defect?
c) How this defect is corrected, write it in brief?

A person is unable to see objects distinctly placed within 50 cm from his eyes.
(a) Name the defect of vision the person is suffering from and list its two possible causes.
(b) Draw a ray diagram to show the defect in the above case.
(c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm.
(d) Draw a labeled diagram for the correction of the defect in the above case.
Give Reason:
When you enter into a dark room from bright because of sunlight, you can not see things for a few seconds.
Study the following diagram carefully and then answer the questions that follow. The diagram is depicting a defect of the human eye :

(i) Identify the defect shown in the diagram.
(ii) Give two possible reasons for the above defect.
Given below is a diagram showing a defect of vision. Name the defect of vision and draw an accurately labelled diagram to correct this defect.

