Which of the following best identifies simple squamous epithelium, and what is its primary function?

• A. A single layer of tall, column-like cells; specialized for absorption and secretion
• B. A single layer of flat cells; allows for rapid diffusion and filtration
• C. Multiple layers of flat cells; forms the outer layer of the skin
• D. Multiple layers of cube-shaped cells; provides protection against abrasion

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the structure of simple squamous epithelium. Simple squamous epithelium consists of a single layer of flat, thin cells. These cells are closely packed and have a flattened nucleus, which is characteristic of this tissue type.
2. Step 2: Identify the primary function of simple squamous epithelium. Due to its thin and flat structure, this epithelium is specialized for processes that require rapid diffusion or filtration, such as gas exchange in the lungs or filtration in the kidneys.
3. Step 3: Compare the descriptions provided in the options. Look for the option that matches the structural and functional characteristics of simple squamous epithelium: a single layer of flat cells and its role in rapid diffusion and filtration.
4. Step 4: Eliminate incorrect options. For example, 'a single layer of tall, column-like cells' describes simple columnar epithelium, which is specialized for absorption and secretion. Similarly, 'multiple layers of flat cells' describes stratified squamous epithelium, which provides protection, and 'multiple layers of cube-shaped cells' describes stratified cuboidal epithelium, which offers protection against abrasion.
5. Step 5: Select the correct answer based on the structural and functional match. The correct description is 'A single layer of flat cells; allows for rapid diffusion and filtration,' which accurately identifies simple squamous epithelium and its primary function.