Epithelial Cells II Flashcards
Epithelial Classification Based on….
- shape
- layering
Epithelial types
- simple squamous
- simple columnar
- stratified squamous
- pseudostratified columnar epithelium
Simple squamous info
e. g. lung alveolar, mesothelium
- flat = squamous
- single layer = simple
Simple Cuboidal Info
e.g. kidney collecting duct
Cuboidal = as wide as tall
Simple Columnar Info
e.g. enterocytes
Columnar = taller than wide
Stratified Squamous Info
- various layers of cells
- cells have a variety of shapes but the surface cells are used for description.
- two main types
keratinizing e.g. epidermis
non-keratinizing e.g. linings of the mouth.
Pseudostratified Columnar Epithelium
e. g. upper airway bronchi epithelium and various ducts in the urinary and reproductive tracts
- all cells are in touch with the basal lamina
- often ciliated
Cell surfaces
- apical
- basal
- lamina
Function of Polarity
to ensure that the secreted products are delivered to the correct tissue compartment.
Secretory Methods
1) Constitutive - secretory vesicles as, they are formed, move directly to the plasma membrane and release their contents e.g. production of plasma proteins by hepatocytes
2) stimulated - secretory vesicles are stored in the cytoplasm and only fuse with the plasma membrane to release their contents when stimulated e.g. adrenaline release from adrenal medulla
Skin Layers
- epidermis
- dermis
- hypodermis
Keratinizing Definition
no nuclei visible in the surface layer cells. They are dead cells and are made tough by the production of several keratins proteins and lipids.
