Epithelial tissue MCQ - Practice Questions with Answers

• Epithelium refers to the tissue composed of one or more layers of cells covering the external and internal surfaces of various body parts. 
• The term epithelium was given by Ruysch to describe tissues that grow on other tissues. 
• Location: Epithelial tissues are found to be present on external and internal exposed surfaces of the body parts where they form a protective covering. 
• Origin: The origin of epithelial tissue is from all the three germ layers i.e. ectoderm, mesoderm, and endoderm.

Features of epithelial tissues:

• Epithelial tissues are made up of variously shaped cells that are closely arranged in one or more layers.
• The cells of epithelial tissues have only a little intercellular space in between them and they are held together by intercellular junctions between them.
• Blood vessels are absent in epithelial tissue, however, underlying connective tissue possesses blood vessels. 
• The epithelial tissue rests on a thin noncellular basement membrane. 
• Epithelial tissues have good regeneration power.

Basement membrane:

• The basement membrane consists of two layers i.e. Basal lamina and the fibrous or reticular lamina
• Basal lamina: Outer thin layer composed of mucopolysaccharides and glycoprotein. 
• Fibrous lamina: Inner thick layer consisting of collagen fibers of underlying connective tissue.
• The function of the basement membrane provides elastic support and selective chemical exchange between epithelial tissues and surrounding blood vessels.