Epithelium tissue Flashcards
What are the 4 primary tissues
Nervous tissue, muscle tissue, epithelium tissue and connective tissue
What is the origin of the tissue. What are the 3 layers
Embryonic germ layer.
Ectoderm
Mesoderm
Endoderm
What does the ectoderm form
surface facing external environment
e.g. skin
What does the mesoderm form
Lining of cavity not exposing to external environment
Lining og kidney tubules, endothelium of blood vessels, mesothelium that covers the lungs, abdomen and heart
What does endoderm form
Lining of body cavity and hollow passageway
E.g. GI tract, respiratory tract
What are the 4 functions of epithelium tissue
- Protection
–>Form physical barrier with the connective tissue beneath - Secretion (Grandular epithelium)
- Sensation (retina and
- Absorption and excretion
What is between the connective tissue and epithelium tissue
Basement membrane
Is there any vascular tissue in epthelium
No
How can epthielium tissue obtain oxygen and nutrients
From the conective tissue beneath (which is highly vascularized)
What are the 3 functions of basement membrane
Act as a glue to connect epithelium tissue and connective tissue
Perform tissue-specific functions
Guiding cell migration during repair by attracting them
What are the layer(s) of basement membrane named and from.
Basal lamina: From secretion of epithelium tissue, Collagen IV
Reticular lamina
From secretion of fibroblast of connective tissue
Collagen III
What are the 6 characteristics of epthielium tissue
- Rest on basement membrane
- Avascular, dependent on the connective tissue beneath for material exchange
- With junctional complex
- Exhibit functional and morphological polarity
- Contains cyotkeratin
- With little or no intercellular matrix
How can epithelium tissue be classified according to the shape of epithelial cell
Squamous (flat)
cuboidal (Cubic)
columnar (Like column)
What are the characteristics of the 3 cell types
Squamous has flattened nuclei which is parallel to the Epithelium
Cuboidal is like a square with spherical nuclei
Columnar has nuclues closer to Basal side
How can epithelium tissue be classified according to the number of layer of cells
Simple (1 layer)
Stratified (>1)
Psedostratified (Like >1 but only 1 actually)
transitional (stretchable and more than 1 layer)
What is simple squamous epithelium for. Example
Material exchange, absorption and secretion
Lining in heart, blood vessels and lymphatics, lining of peritoneal and pleural cavity
Simple Cuboidal?
Secretion, excretion and absorption
–> Pancreatic duct, PCT (Proximal Convoluted Tubule)
Simple columnar
Transport of fluid, secretion, absorption
Lining of intestine, gall bladder
Simple ciliated columnar
Fallopian Tube, ie oviduct to sweep the ovum to uterus
What can Stratified squamous epithelium be further classified into
Keratinized or non-keratinized
What does non-keratinized Stratified squamous epithelium
For protection, containing superficial layer of squamous cells containing nuclei (alive)
Uterine cervix surface