Lecture 5 Epithelial Tissue Flashcards
What is a tissue?
Collection of similar cells of the same origin to perform a certain function
What are the 4 tissue types?
Epithelial Tissue Connective Tissue Muscle Tissue Nervous Tissue
What is epithelial tissue?
a cell layer with a free surface; lining a cavity or some body surface that sit on thin layer of extracellular matrix (ECM)
What are the 3 origins of epithelia and where they can be found.
Endodermal, Gut + accessory organs Urinary, bladder + respiratory Mesodermal, - kidney -reproductive tract Ectodermal - end of digestive tract - epidermis
What are the 4 functional properties of epithelia?
1) Covering, lining, protecting surface –> barriers, 2) transport: absorption + secretion, 3) contractile – myoepithelial, 4) sensory – neuroepithelial
______ are a thin layer of ECM and semipermeable barrier that support + polarity to epithelium
basement membrane
What is this image of? What stain is used?
Bowman’s capsule in kidney, basement membrane stained with Picrosirius-hematoxylin (PSH) but PAS would work)
______ is made up of large glycoproteins, anchor epithelia by integrins and use type IV collagen. ______ is felt like tyoe III collagen.
Basal lamina, reticular laminae,
Hemidesmosomes (H) bind the basal surface of the epithelial cell
What structure is indicated in this image?
Terminal bar
What is the function of gap junctions?
Communication: electrical, movement of molecules, signal nutrients
_______ are surface specializations found in apical membrane (brush border), glycohelix
microvilli
What is the function of microvilli?
Increase surface area, absorption epithelial Presences of enzymes (sieve)
______ increase absorption capacity, by increasing surface area, are very long microvilli and are a core of actin filament
stereocilia (not true cilia)
What are the function of stereocilia?
increase SA
______ are motile, longer then microvilli and found in the respiratory tract and reproductive tract that is involved with movement and mixing
Cilia
______ epithelia are a single layer flat that has a bulging nucleus
simple squamous
______ are a thin, square-shaped epithelium
Simple cuboidal
______ epithelia are a thin layer that is taller than is wide, that are specialized for absorption
Simple columnar
______ have two or more layers, the top right image is most common, what is it?
stratified, stratified squamous
______ are a keratinized dead layer of squamous cells. What is the classification of the image?
stratum corneum, keratinized stratified squamous epithelium
________ have abilities to withstand hypertonic effects. _____ state has a bulging appearance.
transitional, undescended
______ appears to have several layers, but basal ends rest on BM.
Pseudostratified,
columnar
______ are unicellular glands that produce mucin granule and is important for lubrication
Goblet cells
Why is H&E poor and PAS good when staining goblet cells?
b/c staining carbohydrate
True or False: Ion and water transport across epithelia can occur in either direction, depending on which tissue is involved.
True
______ cells have a lot of mitochondria for transport and have various structure in increase SA (microvilli, infolding) .
Absorptive cells
