Tissues And Cells Flashcards
What is the definition of tissues?
Groups of cells of the same type and function working together
What are the 4 types of tissues?
Epithelial
Connective
Muscle
Nerve
Definition of Epithelial tissue
Covers tissue for all of the ducts and body cavities in the body including mouth, blood vessels, thorax and bladder
What are the 6 main functions of Epithelial tissues?
Protects, covers and lines
Filters biochemical substances
Absorbs nutrients
Provides sensory output
Manufacturers secretion
Manufactures excretion
What are the characteristics of Epithelia?
Each Epithelia cell has an apical surface and a basal surface
Definition of Apical surface?
Faces the lumen or outside of the organ
Definition of Basal Surface
Faces the basal lamina and blood vessels
Remember: Basal Surface=Basement, attaches the cell to the interior mechanisms of the body
How are lateral surfaces connected to neighboring cells
Junctional complexes
Epithelial Cells are…
Avascular
Most Epithelial cells are…
Innervated
Matrix filled channels provide cells with
Nutrients
The plasma membranes are connected via ____ to create a strong network of communication
Junctions
Three major types of cellular junctions
Tight Junctions
Desmosomes
Gap Junctions
What are tight junctions formed by
The fusion of the outermost layers of the plasma membranes of adjoining cells
What tissues are tight junctions found in
Found in tissues in which there can be no leaks, such as, urinary bladder and digestive tract
How are Desmosomes formed
Mechanical coupling formed by filaments that interlock with one another
Tonafilaments exted from the ____ into the ____ (Desmosomes)
Plaque and Cytoplasm
What type of tissues are Desmosomes found in
Tissues that undergo repeated episodes of tension and stretching (skin, heart, uterus)
Meshwork of fibers that cements the epithelial cells to the underlying connective tissues
Basement Membrane
Also called Basal Lamina
Basement Membrane
Basement Membrane helps prevent the ____ from being torn off by intraluminal pressures (pressures against the cell)
Cell
Basement Membrane acts as a partial barrier between the ____ cells and the underlying ____ tissue
Epithelial and Connective
Surface Specializations (4 types)
Smooth
Microvilli (Smooth border)
Cilia
Keratin
Found in the gut. They increase surface area and allow for greater surface for absorption of nutrients and secretions
Microvilli
Found in the respiratory tract and the oviduct to help move objects along because ____ are an aspect of locomotion.
Cilia
Tissue that increase the surface area and the Microvilli are these tiny little finger like projections from the Epithelial cells that increase surface area for the cell itself (like a brush border)
Villi
The Epithelial cells of the outermost layer of the skin get impregnated with _____ in order to become waterproof and create a barrier.
Keratin
What characteristics are Epithelial tissues classified based on
Number of layers of cells
Shape of the cells
Prescience if surface specializations
Names for the amount of layers epithelial tissues (cells) can have
Simple (one layer)
Stratified (more than one layer)
Names for the shapes of the cells
Squamous-Flat
Cubodial-Cube shaped
Columnar-Tall