Epithelial tissues

Definition

Epithelial tissues are layers of cells that cover body surfaces and line internal organs and cavities. They serve as protective barriers, aid in absorption, secretion, and sensation.

5 Must Know Facts For Your Next Test

1. Epithelial tissues are classified based on the shape of cells (squamous, cuboidal, columnar) and the number of cell layers (simple, stratified).
2. The basement membrane anchors epithelial tissue to underlying connective tissue.
3. Epithelial cells have a high rate of regeneration due to their exposure to friction and external environment.
4. They play a role in protecting against microbial invasion and dehydration.
5. Some epithelial cells have specialized structures like cilia or microvilli to enhance their function.

Related terms

Basement Membrane: A thin layer that anchors epithelium to underlying connective tissue.

Cilia:

Hair-like projections on some epithelial cells that help move substances across the cell surface.

Microvilli: Small finger-like extensions on some epithelial cells that increase surface area for absorption.