Epithelial Tissue

Epithelial Tissue

A diverse group of tissues that covers body surfaces, lines cavities, and forms glands.

Apical Surface

The surface of epithelial cells that is exposed to a body cavity, internal organ, or the exterior of the body.

Lateral Surfaces

The surfaces of epithelial cells that face adjacent cells on either side.

Basal Surface

The deep surface of epithelial cells that is attached to underlying tissues.

Cuboidal Cells

Epithelial cells that are as tall as they are wide, often involved in secretion or absorption.

Columnar Cells

Tall epithelial cells that protect underlying tissues and may have cilia or microvilli for secretion and absorption.

Simple

A single layer of identical epithelial cells.

Simple Squamous

Flat epithelial cells found in areas like the heart and lungs, facilitating diffusion.

Simple Cuboidal

Cube-shaped epithelial cells involved in secretion and absorption.

Simple Columnar

Rectangular-shaped epithelial cells found in the alimentary tract, specialized for absorption and secretion.

Simple Ciliated

Epithelial tissue with cilia that aids in movement, found in respiratory passages.

Stratified Epithelium

Epithelial tissue composed of multiple layers of cells.

Keratinized Stratified

Epithelial tissue that is dry and resistant to wear, found in skin, hair, and nails.

Non-Keratinized Stratified

Epithelial tissue that is moist, found in the lining of the mouth, pharynx, esophagus, and vagina.

Transitional

Epithelial tissue with pear-shaped cells that can stretch, found in the urinary system.

Endocrine Glands

Glands that secrete hormones directly into the bloodstream without using ducts.

Exocrine Glands

Glands that secrete substances into ducts that empty onto surfaces or into hollow organs, such as mucus and saliva.