The purplish red pigment rhodopsin contained in the rods type of photoreceptor cells of the human eyes is a derivative of
1. vitamin-C
2. vitamin-D
3. vitamin-A
4. vitamin-B
Which one of the following is the correct difference between rod cells and cone cells of our retina?
|
Rod cells |
Cone cells |
||
|
1. |
Distribution |
More concentrated in centre of retina |
Evenly distributed all over retina |
|
2. |
Visual activity |
High |
Low |
|
3. |
Visual pigment contained |
Lodopsin |
Rhodopsin |
|
4. |
Overall function |
Vision in poor light |
Color vision and detailed vision in bright light |
Match the following columns and select the correct option :
| Column I | Column II | ||
| (a) | Rods and cones | (i) | Absence of Cones photoreceptor cells |
| (b) | Blind Spot | (ii) | Cones are densely packed |
| (c) | Fovea | (iii) | Photoreceptor cells |
| (d) | Iris | (iv) | Visible coloured portion of the eye |
| (a) | (b) | (c) | (d) | |
| 1. | (iii) | (i) | (ii) | (iv) |
| 2. | (ii) | (iii) | (i) | (iv) |
| 3. | (iii) | (iv) | (ii) | (i) |
| 4. | (ii) | (iv) | (iii) | (i) |
The major refractive surface in the human eye is the:
1. Anterior surface of cornea
2. Posterior surface of cornea
3. Anterior surface of lens
4. Posterior surface of lens