Tissues - Epithelium Flashcards
What is the function of simple cuboidal epithelia?
Absorption and secretion
What is the function of simple columnar epithelia?
Absorption and secretion
What are globlet cells?
Single celled Gland that secretes mucus
Where are globlet cells normally found?
Simple columnar and pseudostratified
What is the function of stratified squamous non-keratinised epithelium?
Protection against abrasion and wear
What is the function of pseudostratified columnar epithelium?
Cilia transport things along the apical surface of the cell membranes
Shape of top layer of cells and nuclei: simple squamous
Flat cells
Nuclei bulge at apical surface
What is the function of simple squamous epithelium?
Allows rapid transport/exchange of fluids and gases, simple barrier
Shape of top layer of cells and nuclei: stratified squamous non keratinised
Flat surface cells
Nuclei may bulge at apical surface of cell
Shape of top layer of cells and nuclei: simple columnar
Columnar cells
Nuclei sausage shaped and sit towards the basal surface
Shape of top layer of cells and nuclei: pseudostratified columnar
Columnar cells
Nuclei positioned at many different levels and may exhibit different shapes
Shape of top layer of cells and nuclei: simple cuboidal
Cuboidal cells
Rounded nuclei
Microvilli sometimes present
What are the different domains of epithelium?
Apical
Lateral
Basal
Where is simple cuboidal epithelium found?
- surface of the ovary
- kidney tubules
- thyroid follicles
Where is simple squamous epithelium found?
- blood vessels
- kidneys
- lungs
Where is pseudostratified columnar epithelium found?
- trachea and bronchi
- vas deferens and epididymis
Where is stratified squamous (keratinised) epithelium found?
- epidermis
Where is stratified squamous (non-keratinised) epithelium found?
- oral cavity
- oesophagus
- vagina
What is the function of transitional epithelium?
Stretches to allow distension of the urinary tract, protects underlying tissues from osmotic damage from urine
What characterises transitional epithelium?
Binucleate cells on top layer
What is a basement membrane?
- thin layer of intercellular material (50-100nm)
- manufactured by epithelium and comprised of various proteins
What are the functions of a basal membrane?
- structural attachment
- semi-permeable selective barrier
How is the basal membrane connected?
- hemidesmosomes
- underlying layer of connective tissue fibres
Which cells have cilia on apical surface?
- pseudostratified
- simplecolumnar
What makes up a brush border?
Microvilli
What are the functions of the lateral domain of epithelium?
- resists stress
- controls what can go into the cell (barrier)
- communication between cells
Cells of non-keratinised stratified squamous
- nuclei bulge at apical surface
Cells of keratinised stratified squamous
- no nuclei