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प्रश्न
Write the function of the following part of the human eye: ciliary muscles
उत्तर
The function of ciliary muscles:- When these muscles are relaxed, the lens becomes thin. Thus, its focal length increases. This enables us to see distant objects clearly. When you are looking at the objects closer to the eye, the ciliary muscles contract. This increases the curvature of the eye lens. The eye lens then becomes thicker. Consequently, the focal length of the eye lens decreases. This enables us to see nearby objects clearly.
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संबंधित प्रश्न
Answer briefly:
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Choose the correct answer.
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- What are the values shown by the teacher?
Match the following:
| Column - I | Column - II |
| 1. Retina | a. Pathway 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 | f. Power of accommodation |
The figure given below refers to the vertical section of the eye of a mammal. Study the figure carefully and answer the following questions.
 |
- Label the guidelines shown as 1 to 10.
- Write one important role of parts shown as 3 and 7.
- Write one structural difference between the parts shown as 9 and 10.
- Mention one functional difference between the parts shown as 6 and 8.
