BMS08-1001 Epithelial Tissue Flashcards
What do epithelial tissue exist as?
Sheets
What do they rest on?
BM
What makes the BM?
ECM
What joins the BM to the epithelium?
Connective tissue
What 4 things are they classified by?
Cell shape
Layer structure
Surface specialisation
Special locations or functions
What are the 3 cell shapes?
Squamous
Cuboidal
Columnar
What are the 3 layer structures?
Simple
Pseudostratified - rectangular with the nucleus at the bottom
Stratified
What are the 3 surface specialisations?
Ciliated
Brush border
Keratinised
What are the 2 special location/functions?
Respiratory- ciliated columnar with goblet cells
Transitional- urinary tract has stratified squamous or cuboidal
How do glands originate?
Invagination did epithelium
How does an epithelial growth form a gland?
It turns in mesenchyma which buds off to be a gland or joins to an excretory duct
Name some forms of exocrine glands
Simple tubular
Simple acinar
Simple branches acinar
Simple branches tubular
3 exocrine secretion mechanisms
Merocrine
Apocrine
Holocene
Merocrine
Vesicles open at CSM and secretory product is released
Apocrine
Part of the cells cytoplasm is lost her itv the secretory product
Give an example of an apocrine gland
Sweat glands
Prostate glands
Holocrine
Release of entire secretory cell
Give an example of holocrine secretion
Sebaceous glands
3 functions of cell junctions
Keeps sheets tightly bound
Selective barrier
Communication
Tight junction
Seals neighbouring cells in epithelial sheets to prevent leakage of molecules
Adherens junction
Joins actin bundle in one cell to a bundle in another
Desmosome
Joints intermediate filaments between neighbours
Gap junction
Allows passage of small water soluble ions and molecules
Hemidesmosome
Anchors intermediate filaments in the cell to the BM