Which statement about the RPE's cellular organization is true?

Which statement about the RPE's cellular organization is true?

• A. A single layer of hexagonal cells densely packed with pigment granules
• B. Multiple layers with little pigment
• C. A nerve tissue layer
• D. Highly vascularized tissue

Answer: (C)

The retinal pigment epithelium is a single, continuous layer of hexagonal, pigmented epithelial cells that are densely packed with pigment granules. This monolayer sits between the photoreceptor outer segments and the choroid, connected by tight junctions that help form the outer blood-retinal barrier. The pigment helps absorb stray light and reduce glare, while the epithelial arrangement supports essential functions like phagocytosis of photoreceptor outer segments and recycling of visual pigments. It is not neural tissue and it is not highly vascularized; nourishment comes from the underlying choroidal circulation, while the RPE itself remains avascular.

The retinal pigment epithelium is a single, continuous layer of hexagonal, pigmented epithelial cells that are densely packed with pigment granules. This monolayer sits between the photoreceptor outer segments and the choroid, connected by tight junctions that help form the outer blood-retinal barrier. The pigment helps absorb stray light and reduce glare, while the epithelial arrangement supports essential functions like phagocytosis of photoreceptor outer segments and recycling of visual pigments. It is not neural tissue and it is not highly vascularized; nourishment comes from the underlying choroidal circulation, while the RPE itself remains avascular.