Question

Which prevents internal reflection of light in the eyes?
A) Choroid
B) Cornea
C) Sclera
D) Conjuctive
E) Ciliary body

Answer 1

Internal reflection is the phenomena seen in the eyes in which light ray within the medium is reflected from the surrounding surface back into the medium.

Complete step by step answer:
a. Cornea is the colourless outermost part which surrounds the eyes. The light enters into the eye through this layer and its main function is to focus the incoming light.
b. Choroid: It is the vascular layer of the eye, containing connective tissues that lie between the retina and the sclera whose main function is to prevent internal reflection within the eye.
c. Ciliary body: It is the extension of iris which hold the crystalline lens in position and it also helps in modifying the curvature of the lens.
d. Conjunctiva: it is present on the back of the eyelid that provides lubrication and protection to the eye. Whenever eyes blink, eyelids spread tears on the eye surface to keep it lubricated and protected from the microbes as it has anti-microbial property.
e. Sclera: It is the opaque white portion of the eye which can be visible from outside, and it is in the direct contact with the cornea. Its main function is to provide protection to the eyes.
Hence, the correct answer is option (A).

Note: Other important structures of an eye are as follows:
i. Iris: It is the dark muscular diaphragm which is present between the cornea and the lens and its function is to control the size of the pupil.
ii. Pupil: It is the small hole present in between the iris, and it acts as the passage for the light to enter in eyes. In case of dim light, its size widens to allow maximum light to enter, and in case of bright light, it narrows itself to let the only required amount of light to come.
iii. Retina: It is the posterior portion of an eye on which an image is formed and it is a light-sensitive surface as it contains a light-sensitive cell called cones and rod.