The Human Eye and Colourful World

Gap-fill exercise

  
Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
The black opening between the aqueous humour and the eye lens is called .

The muscular diaphragm that controls the size of the pupil is .

The ability of eye lens to adjust its focal length to form a sharp image of the object at varying distances on the retina is called of the eye.

The image formed on the retina of the human eye is real and .

Refraction of light by the earth’s atmosphere due to variation in air density is called .

The deflection of light by minute particles and molecules of the atmosphere in all direction is called of light.

One cannot see through the fog, because light is scattered by the .

At noon the sun appears white as light is least .

When light rays enter the eye, most of the refraction occurs at the outer surface of the .

The least distance of distinct vision for a eye is 25cm.

The defect of vision in which a person cannot see the distant objects clearly but can see nearby objects clearly is called .

The splitting of white light into different colours on passing through a prism is called .

The medical condition in which the lens of the eye of a person becomes progressively cloudy resulting in blurred vision is called .

Very fine particles scatter more of colour.

Red light is used for signals as it is scattered.

Bi-focal lens is used to correct refractive error.

Hypermetropic eye is corrected by using lens.

The dispersion of white light occurs because colours of white light at different through the glass prism.

A lens of higher focal length has .