This is the middle layer of the eyeball and it is composed of the choroid, ciliary body and iris.
The choroid is a layer of the eye deep to the retina and superficial to the sclera. It provides oxygen and nutrients to the retina through its extensive network of capillaries. The retina itself does not have a huge vascular supply, because the vessels would interfere with the formation of the image in the eye. This is why the choroid is necessary. The choroid is also very heavily pigmented due to an abundance of melanin. This increased pigment allows the choroid to absorb excess light and minimize reflections within the eye. The choroid along with the iris and ciliary body make up what is known as the uveal tract.
As the sclera and choroid reach the front part of the eye, they become thinner and more transparent. The sclera thins out to form the cornea, which is the clear outermost layer of the eye that allows light to enter. The choroid also becomes thinner and gives way to the ciliary body and iris in the front part of the eye.
choroid - a highly vascular membrane in the eye between the retina and the sclera; a dark pigmentation minimizes the scattering of light inside the eye.(http://www.thefreedictionary.com/choroid)
The pigmented tunic you are referring to is the choroid, which contains melanin that absorbs excess light and prevents it from scattering within the eye. This helps to improve visual acuity and reduce glare.
choroid
No, the choroid is not the pigmented layer of the eye. The pigmented layer is called the retina, specifically the pigmented epithelium layer of the retina. The choroid is a vascular layer located behind the retina that provides oxygen and nutrients to the retina.
Choroid
choroid
Choroid cysts primarily occur in the eye, specifically in the choroid layer of the eye, which is located between the retina and the sclera. However, similar cystic structures can also appear in other parts of the body, such as the brain (e.g., choroid plexus cysts). While the term "choroid cyst" is most commonly associated with the eye, it's important to recognize that cysts can form in various tissues and organs.
choroid
choroid
choroid is black in colour with a lot many nerve fibres to nourish the organ that is eye.
Choroid
The Choroid.
Absorbs light, and protects your eye.
Absorbs light, and protects your eye.