Question

Write the location of the choroid layer,iris and ciliary body.​

Answer 1

Information about Choroid Layer

• This layer lies just below the sclerotic layer.

• Mamimum pigment cells are present in this layer.

• Abundant blood vessels are present in this layer.

• It prevent from internal reflection of the light for the eyeball.

• It provides nourishment to the retina.

Information about Iris

• It is present on the front of the lens.

• Pupil is the part which covers the iris.

• Opening and closing of the pupil is controlled by the fibres of the iris.

• Iris is originated from ectodermal muscles on the other hand body muscles originate from mesoderm.

• In the eyeball light comes through the pupil part.

Information about Ciliary Body

• Lower swollen part of the limbus is ciliary body.

• It help in holding of the eye lens.

• Choroid layer is connected with its inner end.

• Its outer end is attached with the sclera and corneal junction.

Answer 2

Answer:

Iris :-

• In humans and most mammals and birds, the iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil.
• Thus the amount of light reaching the retina. Eye color is defined by that of the iris.
• In optical terms, the pupil is the eye's aperture, while the iris is the diaphragm.

Choroid :-

• The choroid, also known as the choroidea or choroid coat, is the vascular layer of the eye, containing connective tissues, and lying between the retina and the sclera.
• The human choroid is thickest at the far extreme rear of the eye (at 0.2 mm), while in the outlying areas it narrows to 0.1 mm.
• The choroid provides oxygen and nourishment to the outer layers of the retina.
• Along with the ciliary body and iris, the choroid forms the uveal tract.

Ciliary body :-

• The ciliary body is a part of the eye that includes the ciliary muscle, which controls the shape of the lens, and the ciliary epithelium, which produces the aqueous humor.
• The vitreous humor is produced in the non-pigmented portion of the ciliary body.
• The ciliary body is part of the uvea, the layer of tissue that delivers oxygen and nutrients to the eye tissues.
• The ciliary body joins the ora serrata of the choroid to the root of the iris.