epithelium Flashcards
4 basic types of tissue
epithelial,
Connective,
muscular, and
nervous.
Highest to lowest order of extracellular matrix of tissues
Connective
muscle
epithelial
nervous
a 3D network of extracellular macromolecules, such as collagen, enzymes, and glycoproteins, that provide structural and biochemical support of surrounding cells.
The Extracellular Matrix
What consists ECM?
protein fibers (such as collagens and elastic fibers) ground substance
a complex of anionic, hydrophilic proteoglycans, glycosaminoglycans (GAGs), and multiadhesive glycoproteins (laminin, fibronectin, and others)
ground substance
provides the medium for the exchange of nutrients and metabolic wastes between cells and the blood supply.
ground substance
Such glycoproteins help stabilize the ECM by binding to other matrix components and to __ in cell membranes.
integrins
2 main groups of epithelial tissues
covering (or lining) epithelia
Secretory (glandular) epithelia
cover the external surfaces of the body, line the internal cavities
covering (or lining) epithelia
form various organs and glands, and line their ducts
Secretory (glandular) epithelia
Epithelial cells are in contact with each other, either in a __ or __
single layer or
multiple layers
The structure of _____, however, differs from organ to organ, depending on its location and function.
lining epithelium
THE PRINCIPAL FUNCTIONS OF EPITHELIAL TISSUES
• Covering, lining, and protecting surfaces (eg, epidermis)
• Absorption (eg, the intestinal lining)
Secretion (eg, parenchymal cells of glands)
True or false: Epithelium is vascular.
FALSE
Epithelium is nonvascular, that is, it does not have blood vessels
_____________ diffuse from the blood vessels located in the underlying connective tissue to the epithelium
Oxygen, nutrients, and metabolites
Because the lipid-rich membranes of epithelial cells are frequently indistinguishable with the light microscope, the number and shape of the stained nuclei can indicate _________
cell density and shape.
The nuclei also allow one to determine the ____ in an epithelium, a primary morphologic criterion for classifying epithelia.
the number of cell layers
