The layer of the wall of the eye that contains blood vessels that supply nutrients to the sheet of photoreceptors at the back of the eye and becomes the iris at the front of the eye is the
a. sclera. b. retina. c. vitreous humor. d. aqueous humor. e. choroid.

The correct answer is E.

Explanation:

The choroid is a vascular layer of the eye that lays between the retina and the sclera. Its main function is to supply oxygen and nutrients to the outer layers of the retina. The layers of the choroid are:

•Haller's layer

•Sattler's layer

•Choriocapillaris

•Bruch's membrane  (in contact with the retinal pigment ephitelium)

The choroid is part of the uveal tract, which also contains the iris and the ciliary body.

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