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प्रश्न
Mention if the following statement is true (T) or false (F) Give reason.
yellow spot of the retina is the region of colour vision
विकल्प
True
False
उत्तर
True
APPEARS IN
संबंधित प्रश्न
Answer briefly:
How do you perceive the colour of an object?
A person got his eyes tested by an optician. The prescription for the spectacle lenses to be made reads :
Left eye : +2.50 D
Right eye : +2.00 D
State whether these lenses are thicker in the middle or at the edges.
Where is the image formed in a human eye?
Where does the greatest degree of refraction of light occur in the eye?
Fill in the following blank with suitable word:
The iris controls the amount of................entering the eye.
A person walking in a dark corridor enters into a brightly lit room:
State the effect on the pupil of the eye.
There are two types of light-sensitive cells in the human eye:
Where are they found?
If you walk from a dark room into sunlight and back again into dark room, how would your pupils alter in size? What makes this happen?
Suggest how your irises help to protect the retinas of your eyes from damage by bright light.
Among animals, the predators (like lions) have their eyes facing forward at the front of their heads, whereas the animals of prey (like rabbit) usually have eyes at the sides of their head. Why is this so?
Name the following:
The part of the eye responsible for its shape.
Name the following:
White part of the eye.
The diagram alongside represents a certain defect of vision of the human eye.
(i) Name the defect.
(ii) Describe briefly the condition in the eye responsible for the defect.
(iii) Redraw the figure by adding a suitable lens correcting the defect. Label the parts through which light-rays pass.
(iv) What special advantage do human beings derive in having both eyes facing forward?
What is the nature of the image that forms on the retina?
For a normal human eye the near point is at _______.
The image of an object at an infinite distance is obtained in a real and erect form through a convex magnifying glass.
Shylesh is a school-going kid studying standard VIII. He is crazy about playing video games on mobile phones. After a couple of months, his eyes turned red and he felt severe pain in his eyes. His science teacher enquired about this and advised his parents to take him to an eye doctor.
- How does excessive usage of mobile phone affect our eyes?
- What are the values shown by the teacher?
What kind of lens is there in our eyes? Where does it form the image of an object?
The innermost layer of human eye is ______.
| Column I | Column II | ||
| 1 | Retina | a | Path way of light |
| 2 | Pupil | b | Far point comes closer |
| 3 | Ciliary muscles | c | near point moves away |
| 4 | Myopia | d | Screen of the eye |
| 5 | Hypermetropia | e | Power of accomodation |
