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प्रश्न
There are two types of light-sensitive cells in the human eye:
To what is each type of cell sensitive?
उत्तर
There are two types of light-sensitive cells in the human eye.
The rods (rod-shaped cells) present in the retina are sensitive to dim light and are responsible for vision in dim light.
The cones (cone-shaped cells) present in the retina are sensitive to bright or normal light and are responsible for colour discrimination and colour vision.
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संबंधित प्रश्न
Answer briefly:
How do you perceive the colour of an object?
Distinguish between: blind spot and yellow spot
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Right eye : −3.50 D
Left eye : −4.00 D
Which lens has a greater focal length?
Fill in the following blank with suitable word:
The iris controls the amount of................entering the eye.
Fill in the following blank with suitable word:
To bring light from a near object to a focus on the retina of the eye, the convex eye-lens need to be made....................
What is presbyopia? Write two causes of this defect. Name the type of lens which can be used to correct presbyopia.
Give scientific reason:
We cannot clearly see an object kept at a distance less than 25 cm from the eye.
Select the odd one in the following series:
Retina, Sclera, Ciliary body, Nephron.
Sketch and label V.S. of a human eye.
Draw a diagram of the human eye as seen in a vertical section and label the parts which suit the following descriptions relating to the:
(i) photosensitive layer of the eye.
(ii) structure which is responsible for holding the eye lens in its position.
(iii) structure which maintains the shape of the eyeball and the area of no vision.
(iv) anterior chamber seen in front of the eye lens.
(v) outermost transparent layer seen in front of the eyeball.
