Which type is a single layer of tall, rectangular cells attached to a basement membrane and lines the stomach?

• A. Columnar epithelium
• B. Compound epithelium
• C. Ciliated epithelium
• D. Simple squamous epithelium

Answer: (A)

Epithelial tissue is described by both the shape of the cells and how many cell layers there are. A single layer of tall, column-shaped cells attached to a basement membrane is simple columnar epithelium. This arrangement is ideal for the stomach because these tall cells can house the machinery for secretion and, with mucus-producing cells, protect the lining from acidic gastric juice. It’s not ciliated, which would have hair-like projections, and it’s not multilayered, so it isn’t compound epithelium. It also isn’t simple squamous, which would be a flat, thin layer better suited for diffusion rather than secretion and protection. Therefore, the best match for the stomach lining is columnar epithelium.