Assertion (A): Rods and Cones are photoreceptors in the sclera of eyeball.

Reason (R): Rods are sensitive to dim light.

1. A is True and R is False.
2. A is False and R is True.
3. Both A and R are True.
4. Both A and R are False.

Keshav enters a dark room from a brightly lit area. He experiences difficulty in viewing objects, but gradually his vision improves.

Explain the role of the photoreceptors in this case.

Chris was watching the display of fireworks in the sky.

(a) Trace the path of the light rays using the following terms:

Fovea, Lens, Conjunctiva, Pupil, Cornea

(b) Name the nerve that carries the impulse for vision to the brain.

The four major steps in seeing an object are:

i. interpretation by the brain.

ii. focussing of image.

iii. entry of light rays.

iv. transmission of nerve impulses from the retina & brain.

The correct sequence will be:

1. i, ii, iii, iv
2. ii, iii, iv, i
3. iii, ii, iv, i
4. iv, i, ii, iii