Question

If the light source infront of an eye becomes bright suddenly
a. The focus of the lens will change
b. Retinal blood supply is cut
c. Vitreous humor becomes fluid
d. Pupil will contract

Answer 1

The eye is one of the sense organs. The eye is an organ of sight. The shape of the eye is spherical and is present in bony sockets in the skull. Through the cornea, light rays enter the eye. The back of the eye on the inside is lined by a thin layer of tissue called the retina. A pupil is the opening through which light passes before reaching the lens.

Complete answer:
- If the light source in front of an eye becomes suddenly bright, then there will be an increase in the amount of light entering the eye.
- Then, the adjustment of the pupil takes place to regulate the amount of light entering into the eye.
- The focus of the lens will be changed according to the light entering the eye.
- Iris regulates the size of the pupil and it contracts to decrease the pupil size.
- The process of regulation of light entering the eye by adjusting the size of the pupil is known as accommodation.
- Retinal blood supply is cut when blood clots block the vein.
- Eye filled with vitreous humor helps it to hold its spherical shape.
- Pupil contracts when bright light falls on the eye so that less light can enter the eye.

Hence, the correct answer is option (D).

Additional information:
- The function of the retina is to receive light that has been focused by a lens, it changes the light into neural signals and these signals are sent on to the brain for visual recognition.
- The pupil constricts when exposed to bright light and it expands in dim light.
- The lens focuses the light rays that pass through it and forms a clear image of objects that are positioned at various distances.

Note: When the light source in front of an eye becomes suddenly bright the focus of the lens is changed by pupil according to the amount of the light entering the eye. When there is a bright light the size of the pupil gets constricted whereas when the eye is exposed to dim light then the size of the pupil dilates. Iris control pupil size. A pupil is present within the iris. The main role of the pupil is to change its size to adjust the amount of light available.