Which tissue type lines body surfaces and cavities and lacks blood vessels?

Which tissue type lines body surfaces and cavities and lacks blood vessels?

• A. Nervous tissue
• B. Muscle tissue
• C. Epithelial tissue
• D. Connective tissue

Answer: (C)

Epithelial tissue lines body surfaces and cavities and is avascular, meaning it has no blood vessels of its own. This tissue forms the outer layer of the skin and the linings of hollow organs and body passages—such as the mouth, esophagus, stomach, intestines, airways, and the inner surfaces of blood and lymph vessels. Because it lacks its own blood supply, nutrients and wastes diffuse to and from the epithelial cells through the underlying connective tissue. Epithelial tissue also serves protective, absorptive, and secretory roles, with cells tightly packed and often arranged in single or multiple layers to suit the location. In contrast, nervous tissue, muscle tissue, and connective tissue all rely on blood vessels and serve different primary functions, so they don’t fit the description of lining surfaces and cavities while being avascular.

Epithelial tissue lines body surfaces and cavities and is avascular, meaning it has no blood vessels of its own. This tissue forms the outer layer of the skin and the linings of hollow organs and body passages—such as the mouth, esophagus, stomach, intestines, airways, and the inner surfaces of blood and lymph vessels. Because it lacks its own blood supply, nutrients and wastes diffuse to and from the epithelial cells through the underlying connective tissue. Epithelial tissue also serves protective, absorptive, and secretory roles, with cells tightly packed and often arranged in single or multiple layers to suit the location. In contrast, nervous tissue, muscle tissue, and connective tissue all rely on blood vessels and serve different primary functions, so they don’t fit the description of lining surfaces and cavities while being avascular.