"choroid" 的定义和意义

What is "choroid"?

The choroid is a layer of tissue located in the back of the eye, between the retina and the sclera. It is rich in blood vessels that provide oxygen and nutrients to the retina, helping to nourish and support its function. The choroid also helps to regulate the amount of light entering the eye by absorbing excess light and reducing glare. Additionally, it contains pigments that contribute to the eye's coloration. The choroid plays a crucial role in maintaining the health and proper functioning of the eye.