EPITHELIAL TISSUE.

Simple Squamous epithelial.

Characteristics: Single-layer of flattened cells and disc-like nuclei and sparse cytoplasm.
Function: diffusion and filteration and provide a slick, friction-reducing lining in the cardiovascular and lymphatic systems.
Found in: Kidneys, glomeruli, lining of heart, blood vessels, lymphatic vessels, and serosae

Simple Cuboidal

Characteristics: One single layer of cubelike cells with large, spherical central nuclei. This single layer of tall cells with oval nuclei may contain many cilia.
Functions: in secretion and absorption.
Found in: Nonciliated line digestive tract and gallbladder. . Ciliated line small bronchi, uterine tubes, and regions in the uterus.
The purpose of the cilia is to help move substances through internal passageways.


Simple Columnar

Characteristics: Single layer cubelike cells with large, spherical central nuclei
Function: in secretion and absorption.
Location: Kidneys tubules, ducts, secretory portions in small glands, and ovary surfaces.


Pseudostratified

Characterisics: Single layer of cels, with a variety of heights; some not reaching the free surface. The nuclei is seen at different layers.

Function: in secretion and propulsion of mucus.
Location: male sperm-carrying ducts (non-ciliated) and in trachea(ciliated) 


Stratified Squamous 

Characteristics: Thick membrane consisting of several layers of cells 

Function: Protection of the underlying areas subject to abrasion
Location: forms the external part of the skin's epidermis (keratinized cells) and the lining of the esophagus, mouth, and vagina (nonkeratinized cells)

Stratified Cuboidal and Columnar

Characteristics: Stratified cubodial is rare in the body, but found in some mammary and sweat glands. It can possibly be two layers thick.
Stratified columnar has limited distribution throughout the body.
Location: pharynx, male urethra, and lining some glandular ducts

Transitional: 

Characteristics: Several layers of cells, bascal cells are cuboidal, surface cells are dome shaped
Function: Stretched to permit the distension of the urinary bladder
Location: lines the urinary bladder, ureters, and parts of the urethra.