Histology epithelium Flashcards
Describe epithelia…
A cohesive sheet of cells resting on a basement membrane.
They form barriers for:
protection, absorption and secretion.
What are the two types of epithelia?
Simple epithelia - single layer of cells on a basement membrane.
Stratified (compound) epithelia - Two or more layers of cells on a basement membrane.
What is this type of epithelia?
Simple epithelia
What is this type of epithelia?
Stratified (compound) epithelia
Describe simple squamous epithelia…
Function: Allows materials to pass through by diffusion and filtration. Secretes lubricating substances
Location: Alveoli in lungs. Lining of the heart, blood vessels and lymphatic vessels.
Describe simple cuboidal epithelia…
Function: Secretion and absorption.
Location: Ducts and secretory portions of small glands. Kidney tubules.
Describe simple columnar epithelia…
Function: absorption and secretes mucous and enzymes.
Location: ciliated tissues (bronchi, uterus, uterine tubes)
non-ciliated tissues (digestive tract and bladder)
Describe pseudo-stratified columnar epithelia…
Function: Secretes mucous
Location: ciliated (respiratory epithelia)
Describe stratified squamous epithelia…
Function: Protects against abrasion.
Location: Oesophagus, mouth, vagina
Describe stratified cuboidal epithelia…
Function: Protective tissue
Location: Sweat glands, salivary glands, mammary glands.
Describe stratified columnar epithelia…
Function: Secretion and protection
Location: male urethra and some glands.
Describe transitional (urothelium) epithelia…
Function: Allows urinary organs to expand and stretch
Location: Bladder, urethra, ureters.
What type of epithelia is this:
Simple squamous
What type of epithelia is this:
Simple cuboidal
What type of epithelia is this:
Simple coloumnar
What type of epithelia is this:
Pseudo-stratified columnar
What type of epithelia is this:
Stratified squamous
What type of epithelia is this:
Stratified cuboidal
What type of epithelia is this:
Stratified columnar
What type of epithelia is this:
Transitional (urothelium)
What is this image showing and what type of epithelium is this?
Peritoneum
Simple squamous
What is this image showing and what type of epithelium is this?
Lung alveoli
Simple squamous
What is this image showing and what type of epithelium is this?
Kidney
Simple cuboidal
What is this image showing and what type of epithelium is this?
Salivary gland
simple cuboidal
What is this image showing and what type of epithelium is this?
Stomach
Simple columnar
What is this image showing and what type of epithelium is this?
Small Intestine
Simple columnar
What structure is this image showing and where is it located?
Microvilli within the small intestine
Describe microvilli…
Microscopic projections on luminal surface of absorptive cells.
What structure is this image showing and where is it located?
Cilia on the Fallopian tubes
What structure is this image showing and where is it located?
Cilia on trachea
Describe cilia…
Microscopic projections on luminal surface of cells. Found in the respiratory tract and the reproductive tract.
What is this image showing and what type of epithelium is this?
Pigmented skin
Stratified epithelia
What is this image showing and what type of epithelium is this?
Oesophagus
Stratified squamous non-keratinising epithelium
What is this image showing and what type of epithelium is this?
Vagina
Stratified squamous non-keratinising epithelium
What is this image showing and what type of epithelium is this?
Thin skin
Stratified squamous keratinising epithelium
What is this image showing and what type of epithelium is this?
Thick skin
Stratified squamous keratinising epithelium
What is the difference between keratinising and non-keratinising stratified squamous epithelium?
Non-keratinising epithelium lacks protein such as keratin in the cells.
What is this image showing and what type of epithelium is this?
Trachea
Pseudo-stratified epithelium
What is this image showing and what type of epithelium is this?
Badder
Urothelium
What is this image highlighting?
Basement membrane in vagina
What is this image highlighting?
Basement membrane in the kidneys.
Describe the basement membrane…
Composed of several extra-cellular proteins (collagen IV, fibronectin).
Can be seen when stained with PAS.
Describe this epithelial junction…
Desmosomes / anchoring / adherent junctions
A plaque that forms physical joins between cells and connects the cytoskeletons of adjacent cells.
They spread forces across several cells.
Describe this epithelial junction…
Tight Junction / Occluding junction
A band like fusion between the cells that does not easily allow molecules to pass through.
They prevent diffusion between cells.
Describe this epithelial junction…
Gap / communicating junctions
Electrical junctions that allow the transfer of small molecules
They electrically couple adjacent cells.
