Question

Consider the following statements in the context of human eye : (a) The diameter of the eye ball is about 2.3 cm. (b) Iris is a dark muscular diaphragm that controls the size of the pupil. (c) Most of the refraction for the light rays entering the eye occurs at the crystalline lens. (d) While focusing on the objects at different distances the distance between the crystalline lens and the retina is adjusted by ciliary muscles. The correct statements are –

In human eye the part which allows light to enter into the eye is –

Mr. Backson, a 55-year-old man, experiences difficulty seeing clearly, especially for reading. He is fade up by blurry vision at close distances, while distant objects appear relatively better. After examination, his eye doctor diagnosed that his eye lens has become less flexible and opaque.

Observe the given diagram of structure of eye and answer the questions based on it.