Question

Select the correct match of the types of neuron given in column-I with its location given in column II.

	Column-I		Column-II
A	Sclera	I	The visible coloured portion of the eye.
B	Choroid	II	Its diameter is regulated by the muscle fibres of the iris
C	Pupil	III	Composed of a dense connective tissue
D	Fovea	IV	Portion of the retina where only the cones are densely packed
E	Iris	V	Contains many blood vessels and looks bluish in colour

A) A-I; B-II; C-III; D-IV; E-V
B) A-III; B-V; C-II; D-IV; E-I
C) A-IV; B-I; C-V; D-II; E-III
D) A-V; B-IV; C-III; D-I; E-II

Answer 1

Hint:
The eyes are complex sense organs. Each eye has a layer of receptors and a system of nerves that conducts impulses from the receptors to the brain. The eyes are spherical structures that are filled with fluid

Complete answer:
The sclera (the white of the eye), is a layer of dense connective tissue made up of mostly collagen fibres and fibroblasts. It provides shape and protects inner parts. Through the sclera, no light can pass. The choroid provides nutrients as well as oxygen to the structures in the eye as it is
a vascular layer. The iris is the pigmented and coloured portion of the eye. The round opening in the centre of the iris through which light enters the interior portions of the eye is a pupil. The iris contains circular muscles that constrict and radial muscles dilate the pupil. A small depression in the centre of the macula lutea(yellowish pigmented spot) is called fovea centralis. In it, the cones are packed densely. There are no blood vessels. Consequently, the fovea is the point where visual acuity is the greatest.

Option ‘B’ is correct

Note:
Pupil acts like the diaphragm of a camera, dilating and constricting the pupil to allow more or less light into the eye. Muscles of the iris are regulated by the autonomic nervous system. Parasympathetic nerve fibres innervate the circular muscles and sympathetic fibres supply the radial muscle.