What kind of lens is present in the human eye?

Name two parts of the eye which refract light rays (or bend light rays).

Name the part of the eye:

(a) Which controls the amount of light entering the eye.

(b) on which the image is formed.

(c) which changes the focal length of eye.

What is the name of:

(a) the curved, transparent front surface of the eye ?

(b) the light-sensitive layer in the eye?

Where is the image formed in a human eye?