Stratified Squamous Epithelium

Stratified Squamous Epithelium

• Function: This is the body’s WEAR-N-TEAR tissue. It is made to take lots low energy friction, exposure to the environment, protect us from fluid loss and invasion.

Simple Cuboidal

• Function: A big secretor! It makes up all types of glands. • Location: There are a few places in the body that you will find that

this tissue absorbs. It is easy to know…just look for the mircrovilli., like the kidney tubes (nephrons).

Stratified Cuboidal

• This tissue secretes and is usually found in sweat glands and larger glands (Endocrine)

Simple Cuboidal: Gland Types

• Endocrine glands: (endo-inside) Makes their product and secretes it into the matrix.

• Capillaries come inside the gland and pick up the product.

The follicular epithelium is primarily simple cuboidal, but some are simple squamous.

Simple Cuboidal: Gland Types

• Exocrine glands: (exo-outside) This type of gland secretes its products using a duct. The product is placed into or onto an open area.

• Examples of exocrine product are saliva, mucous, enzymes, oil/wax, reproductive fluids, and milk.

Simple Columnar

• Function: This tissue is a big absorber! Just look for the microvilli. (I.E. Intestines)

• Location: This tissue is also found in many places in the body with cilia. (I.E. fallopian tubes or epidydimis)

Simple Columnar

• Location: Found ONLY lining the upper respiratory tract (trachea, bronchi, and bronchioles). The cells have cilia in order to sweep debris out of the lungs.

• This tissue also has GOBLET CELLS. These are one-cell glands and they produce mucin. Mucin is a trapping agent.

Stratified Columnar

• Location: This tissue isn’t located in too many places in the body. It is usually found at the ends of the stomach.

• This tissue can be replaced by Stratified Squamous if it is constantly damaged by acid reflux (‘Heartburn’).

Pseudostratified Columnar

• Remember to key on the nuclei! It may seem like this tissue is more than one layer, but it is not.

• The nuclei are all over the place and only give the appearance of being more than one layer!

Stratified Transitional Tissue

• Found in areas where there is a lot more stress like the urinary bladder

• Must be able to stretch from a cuboidal shape (empty) to a squamous shaped appearance (full) and back again

Stratified Transitional Epithelium

• When the urinary bladder is empty, the apex of the cells are rounded and the tissue takes on a cuboidal shape. (Diagram A)

• When the bladder fills with urine and begins to distends, the cells flatten out and become squamous shape. (Diagram B)

Review of epithelial tissues• Simple:

– Squamous– Cuboidal– Columnar

• Psuedostratified columnar (the ‘rule breaker’)

• Stratified:– Squamous– Cuboidal– Columnar

• Transitional (the ‘rule breaker’)