chapter ; Flashcards
tissue that covers surfaces
lines internal surfaces
forms glands
epithelial tissue
tissue that fills internal spaces
provides support
stores energy
transports materials
connective tissue
tissue contracts to produce movement
muscle tissue
tissue carries information as electrical impulses
nervous tissue
layers of cells that cover and line all surfaces of the body
epithelia
structures that produce fluid secretions
glands
-provide physical protection
-control permeability
-provide sensation
-produce specialized secretions
functions of epithelial tissue
-polarity
-cellularity
-attachment
-avascularity
-regeneration
characteristics of epithelial tissue
-move fluids over the epithelium (protection/lubrication)
-move fluids through the epithelium (permeability)
-produce secretions (protection and messaging)
specializations of epithelial cells
epithelial cell is divided into two functional groups
apical surface - exposed to internal or external environment (contains microvilli and cilia)
basolateral surface - includes base (where cell attaches) and sides (where cell contacts neighbors)
polarity of epithelial tissue
many epithelial cells that line internal passageways have this
increase absorption or secretion
microvilli
moves fluids
cilia
integrity is epithelia is maintained by
-intercellular connections
-attachment to basement membrane
-epithelial maintenance and repair
opposing plasma membranes are interconnected by transmembrane proteins called cell adhesion molecules
cell junctions
intercellular connections
specialized areas of plasma membrane that attach a cell
cell junctions
this junction permits free diffusion of ions and small molecules between cells
2 cells held together by transmembrane proteins
gap junction
this junction is formed by the fusion of the outer layers of 2 plasma membranes
prevents diffusion of fluids and solutes between cells
adhesion belt lies deep to this junction and is tied to microfillaments of the terminal web
tight junction
this junction ties adjacent cells together
dense area is connected to cytoskeleton
spot desmosome
this junction attaches a cell to extracellular structures in the basement membrane
hemidesmosome
layer closer to epithelium which restricts movement of proteins and other large molecules from the underlying connective tissue into the epithelium
basal lamina
deeper portion of basement membrane which gives strength and acts as a filter
reticular lamina
the only way the epithelium can maintain structure in extreme environment is by continual division of stem cells
epithelial maintenance and repair
epithelia that contain gland cells specialized for secretion
glandular epithelia