Question

Aqueous humour is secreted by
A. Choroid
B. Ciliary body
C. Retina
D. Lacrimal gland

Answer 1

Aqueous humour is a clear watery fluid seen in the eyes between the eye lens and the cornea. It is a transparent, protein-containing fluid that gives nourishment to the eyes and keeps them inflated. The cornea, lens, avascular tissues in eyes are nourished by the aqueous humour. The main function is to maintain the hydrostatic pressure inside the eyes and helping it to maintain its spherical shape.

Complete answer:
Aqueous humour in the eye is produced by the pars plicata, which is the anterior part of the ciliary body. The aqueous humour is secreted into the posterior chamber of the eyeball into the anterior chamber. The production and secretion of aqueous humour are to be in equilibrium. Any change in the concentration of the fluid can affect the intraocular pressure which damages the eyesight. It prevents the drying up of eyes and protects from dust particles and pathogens. The increased production or the decreased secretion of the aqueous humour will lead to an increase in intraocular pressure which is a major risk in causing glaucoma. It is an optic neuropathy disease caused by the death of retinal ganglion. Severe glaucoma can lead to blindness.
The human eyeball is composed of three layers. The sclera is the external layer of the eye composed of dense connective tissue. The choroid is the middle layer containing many blood vessels and looks blue in colour. The choroid layer is thin over the posterior region of the eyeball and becomes thick in the anterior region to form the ciliary body where the aqueous humour is produced. The ciliary body continues forward to form the opaque, pigmented structure called ‘Iris’. Iris is the visible coloured portion of the eye.
The retina is the third layer of photoreceptor cells seen. Lacrimal glands are tear glands situated above each eyeball, which produces tears which are spread all over the surface each time we blink.
The answer is Ciliary body, option (C)

Note: Apart from the aqueous humour, another fluid is produced inside the eye called the vitreous humour. It is seen between the eye lens and retina. Unlike aqueous humour, it is a thick, jelly-like substance which helps to transmit the light rays to the retina. Both are transparent, clear fluids. Vitreous humour mainly contains salt, sugar, water, collagen etc. Aqueous humour contains proteins, vitamins and other nutrients.