The choroid stains dark as it contains pigments and blood vessels. It is
located underneath the retina. It also lies between the retina and the sclera.
The choroids are very rich in connective tissues( blood vessels) which help
supply the retina with vital nutrients needed for proper eyesight.
The choroids are usually thickest at the extreme rear end of the eye and also helps to maintain a constant eye temperature and volume. This is
important to prevent changes in eye size and temperature which may cause
eye destruction and diseases .
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