State the functions of the following:

(i) Eyelids

(ii) Eyelashes

(ili) Tears

(iv) Iris

(v) Ciliary muscles

Name the following :

(i) Place of best vision in the retina of the eye

(ii) Place of no vision in the retina of the eye

(iii) Kind of retinal cells sensitive to dim light

(iv) The circular opening enclosed by iris

(v) The fibres which collectively hold the lens in position

(vi) Capacity of the eye to focus at different distances

(vii) The kind of lens required to correct near sightedness

(viii) The layer of the wall of the eye-ball that corresponds to the black lining of the box of a camera

Give the reason for the following:

(i) Medicines dropped in the eye flow down into the nose.

(ii) A person from bright sunlight outside enters a poorly lit room and feels blinded for a short while.

Categorise the following parts under

(i) external (ii) middle (iii) internal ear.

Ear drum, hammer, pinna, cochlea, anvil, stirrup, eustachian tube, tympanum, oval window, semi-circular canals.