Animal tissues

Tissue:

A tissue is a group of similar cells specialized for the performance of a common function. They are the group of cells that have similar structure and act together perform a specific function. Group of tissues make up organ in the organisms.

Today we are going through four types of tissues found in animals. You will find useful information related to different types of tissues in animals as well as humans.

Epithelial tissue

Connective tissue

Nervous tissue

Muscle tissue

Today our article will deal with the structure, function, types and detail of epithelial tissue. We will discuss four types one by one in detail.

Epithelial tissue:

Epithelial tissue exists in many structural forms. Epithelial tissue, generally, either covers or lines something and typically consists of renewable sheets of cells. Epithelial tissue covers exterior surfaces of the body, lines internal cavities and passageways and also forms certain glands. Reproductive and urinary system, also digestive tract are covered by epithelial tissue.

Function of epithelial tissue:

General function of epithelial tissue include absorb (e.g. the lining of small intestine , transport (kidney tubules) , excrete (sweat glands) , protect ( skin) , and contain nerve cells for sensory reception.

Epithelial tissue provides the body’s first line of protection from physical, chemical and biological wear and tear. The cells of the epithelium act as gatekeeper of the body controlling permeability and allowing selective transfer of materials. Many epithelial cells are capable of secretion and release mucous and specific compounds. The epithelium of the small intestine secretes digestive enzymes.

Classification of epithelial tissue:

Epithelial tissues are classified according to the shape of the cells and number of cell layers formed. On the basis of cell shape there are following types.

Squamous epithelium: consists of flat cells.

Cuboidal epithelium: consists of cube shaped cells.

Columnar epithelium: consists of column like cells.

On the basis of cell layer they are classified as follow:

Simple epithelium: it is consists of only one layer of cell.

Stratified epithelium: it is consists of more than or many layers of cells.       

 Pseudo stratified epithelium: It describes tissue with a single layer of irregularly shaped cells that give the appearance of more than one layer.