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प्रश्न
With reference to the functioning of the eye, answer the question that follow:
Name the cells of the retina and its respective pigments which get activated in the dark.
उत्तर
In the dark: Cells - rod cells, Pigment - rhodopsin
संबंधित प्रश्न
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 spectacle lenses will converge light rays or diverge light rays.
What is the name of:
the light-sensitive layer in the eye?
What happens to the size of pupil of our eye (i) in dim light (ii) in bright light?
Name the cells on the retina of an eye which are sensitive to (i) bright light (ii) dim light (iii) sensation of colour.
Explain the functions of the following parts of the eye:
(i) cornea
(ii) iris
(iii) pupil
(iv) ciliary muscles
(v) eye-lens
fill in the following blank with suitable word:
A person is short-sighted if his eyeball is too............Spectacles with a .............lens are needed. A person is long-sighted if his eyeball is too............Spectacles with a ................lens are needed. These focus light rays exactly on to the..........
State whether the following statement is true or false:
Rabbit has eyes which look sideways.
Name two animals having eyes:
one the sides of the head.
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?
What is a lacrimal gland?
Give scientific reason:
One can sense colours only in bright light.
Give scientific reason:
We cannot clearly see an object kept at a distance less than 25 cm from the eye.
Give the main function of the following:
Lachrymal glands
What is the nature of the image that forms on the retina?
Give Technical Term:
The cells of the retina that are sensitive to colour.
State the Function:
Conjunctiva
The image formed on the retina of the human eye is ____________.
Match the following:
| 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 accommodation |
Write the main functional activity of the following structure.
Ciliary body and suspensory ligament
Name the following:
Two pigments of the sensory cells.
