Question

Posterior epithelium of cornea is composed of
(A) Simple columnar epithelium
(B) Stratified columnar epithelium
(C) Simple cuboidal epithelium
(D) Simple squamous epithelium

• A. Simple columnar epithelium
• B. Stratified columnar epithelium
• C. Simple cuboidal epithelium
• D. Simple squamous epithelium

Hint:

The corneal endothelium is another name for the posterior epithelium.
Like all endothelial linings (such as blood vessels), it consists of a single layer of flattened cells, which is histologically a simple squamous epithelium.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
The cornea is the transparent anterior portion of the eye's fibrous tunic.
It is composed of five distinct layers: the anterior epithelium, Bowman's membrane, stroma (substantia propria), Descemet's membrane, and the posterior epithelium.

Step 2: Detailed Explanation:
Let us analyze the histological composition of the corneal epithelial layers:
- Anterior Epithelium: This layer is exposed to the external environment and is composed of non-keratinized stratified squamous epithelium.
- Posterior Epithelium (Corneal Endothelium): This is the innermost layer of the cornea, facing the anterior chamber of the eye.
It is composed of a single layer of flattened, polygonal cells.
Histologically, this arrangement is classified as a simple squamous epithelium.
- Functional Role: These cells act as active metabolic pumps, constantly transporting water out of the corneal stroma into the anterior chamber.
This dehydration function (corneal deturgescence) is critical to maintaining corneal transparency. Because these cells have limited regenerative capacity in most adult mammals, damage to this layer can lead to corneal edema and opacity.

Step 3: Final Answer:
The posterior epithelium of the cornea is composed of simple squamous epithelium. This corresponds to option (D).