Tissues Flashcards
List the 6 functions of Epithelial tissue
- Protection - covering + lining
- Filtration - biochemical substances
- Absorption - nutrients
- Sensation - sensory input
- Secretion
- Excretion
List 6 characteristics of of Epithelial Tissue
- Are polar
- Have cell junctions
- Are avascular
- Are innervated
- Have a basal lamina
- Have surface specialization
epithelial cells have a sense of direction relative to surrounding structures
Polarity
epithelial cell surface that faces the lumen
Apical Surface
Body cavity
Lumen
epithelial cell surface that faces the underlying connective tissue
Basal Surface
the attachments between the plasma membranes on the lateral surfaces of neighboring epithelial cells
Cell Junctions
cellular attachments that prevent substances from leaking across the tissue
Tight Junctions
cellular attachments that consist of a strong plaque that cements neighboring cells together
Desmosomes
intermediate filaments that extend from the plaque into the cytoplasm of each cell like anchors to stabilize a desmosome junction
Tonofilaments
junctions that link epithelial cells to the basement membrane
Hemidesmosomes
cellular attachments that link the cytoplasm of neighboring cells together via connexons in order to allow the exchange of ions, electrical signals, and nutrients
Gap Junctions
Transmembrane channel proteins that extend between the cytoplasm of neighboring cells
Connexons
the non-living meshwork of fibers that cements epithelial cells to the underlying connective tissue and allows for the exchange of molecules and substances between the epithelial cells and the connective tissue
Basement Membrane (Basal Lamina)
What is the difference between microvilli and cilia?
Microvilli - fingerlike projections that increase the surface area of the cell and enhance the cell’s ability to absorb or secrete
Cilia - hairlike projections that serve to aid in the transport of materials
What are 4 actions taken by vet staff to treat patients with parvovirus?
- Combat the dehydration
- IV fluid therapy with electrolyte supplements
- Antibiotics
- Anti-vomiting meds
What are the 3 ways epithelia can be classified?
- Number of layers of cells
- Shape of cells in the luminal tissue surface
- Presence of surface specializations
Explain the difference between simple and stratified epithelia
Simple = a single layer of cells
Stratified = multiple layers of cells
Explain the characteristics and structural differences in squamous, cuboidal and columnar epithelial cells
- Squamous - flat + hexagonal cells, central disc shaped nuclei, fragile
- Cuboidal - cubic cells, central round nuclei, fragile, ciliated or smooth
- Columnar - elongated cells, nuclei aligned toward the basement membrane, protective, ciliated or smooth
What is special about pseudostratified columnar epithelial tissue? Give 3 reasons
- Appear stratified > due to not all cells reaching the luminal surface
- Nuclei at different levels across the tissue
- Simple tissue
What is special about transitional epithelial tissue? Give 1 reason
Layer cell shapes are based on the level of tissue distension > relaxed (cuboidal) or stretched (squamous)
the accumulation of a protective, waterproof substance within some epithelial cells
Keratinization
cells that manufacture and store lubricating mucus that is secreted onto the luminal epithelial surfaces in the GI tract
Goblet Cells
specialized protein molecules that remain within the body
Secretions