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