Very Short Question and Answers - Epithelial Tissue

Epithelial tissue is a group of cells that cover body surfaces, line cavities and hollow organs, and form glands.

The main functions of epithelial tissue include protection, absorption, secretion, and sensation.

The two main types of epithelial tissue are simple epithelium and stratified epithelium.

Simple epithelium consists of a single layer of cells and is involved in absorption, secretion, and filtration.

Stratified epithelium consists of multiple layers of cells and provides protection against abrasion and wear.

The types of simple epithelium include simple squamous, simple cuboidal, and simple columnar epithelium.

Simple squamous epithelium is composed of a single layer of flattened cells, allowing for diffusion and filtration.

Simple cuboidal epithelium consists of a single layer of cube-shaped cells, primarily involved in secretion and absorption.

Simple columnar epithelium is made up of a single layer of tall, column-like cells, which often have microvilli for increased absorption.

The types of stratified epithelium include stratified squamous, stratified cuboidal, and stratified columnar epithelium.

Stratified squamous epithelium provides protection against mechanical stress, pathogens, and dehydration.

Glandular epithelium is specialized for secretion and forms the ducts and secretory portions of glands.

Exocrine glands secrete substances onto epithelial surfaces via ducts, while endocrine glands secrete hormones directly into the bloodstream.

Ciliated epithelium is a type of epithelium that has hair-like structures called cilia on its surface, which help in movement of substances.

Transitional epithelium is found in organs such as the bladder, where it allows for stretching and expansion.

The basal lamina is a thin layer of extracellular matrix upon which epithelial tissues rest and provides support.

Epithelial tissues are avascular and receive nutrients through diffusion from nearby connective tissues.

Tight junctions create a barrier that prevents the passage of substances between epithelial cells, maintaining the integrity of the tissue.

Epithelial tissues in the skin provide a protective barrier against environment factors and help in sensation.

Apoptosis is the programmed cell death that helps maintain the integrity of epithelial tissues by eliminating damaged or old cells.