Which tissue type lines blood vessels?

Which tissue type lines blood vessels?

• A. Simple squamous epithelium
• B. Mesothelium
• C. Simple cuboidal epithelium
• D. Endothelium

Answer: (D)

Endothelium is the lining of the interior surface of blood vessels. It’s a specialized, single layer of flat cells that creates a smooth, friction-reducing surface for blood flow and acts as a selective barrier between blood and surrounding tissues. While it’s a type of simple squamous epithelium, endothelium specifically refers to the vascular lining, which is why it’s the correct term for vessels. Mesothelium lines serous membranes like the lining of the chest and abdomen, not blood vessels. Simple cuboidal epithelium forms a single layer of cube-shaped cells found in gland ducts and kidney tubules, not the vascular interior.

Endothelium is the lining of the interior surface of blood vessels. It’s a specialized, single layer of flat cells that creates a smooth, friction-reducing surface for blood flow and acts as a selective barrier between blood and surrounding tissues. While it’s a type of simple squamous epithelium, endothelium specifically refers to the vascular lining, which is why it’s the correct term for vessels. Mesothelium lines serous membranes like the lining of the chest and abdomen, not blood vessels. Simple cuboidal epithelium forms a single layer of cube-shaped cells found in gland ducts and kidney tubules, not the vascular interior.