Gut Histology Flashcards
What does most epithelial tissue line?
cavitities and surfaces
apical side touches the lumen
Basement membrane
normally separates epithelial tissue from connective tissue lamina propria
Is basement membrane an actual membrane?
no
it is made of extracellular material
What does basement membrane bind to?
hemidesosomes
What is main collagen type of connective tissue?
type I collagen
Do epithelial cells contain an abundance of collagen?
no
Does epithelial tissue secrete components of basal lamina?
yes
What are microvilli made of?
actin filaments
What type of cells have microvilli?
intestine
can form a “brush border”
What type of cells have cilia?
respiratory tract cells
important for mucus movement
What is true in general of cilia?
they help with movement
Simple epithelia
single layer of cells, all of which rest on basement membrane
can have different shapes
Where is simple epithelia normally found?
where exchanges occur
such as blood capillaries and air spaces of lungs
Simple squamous epithelial cells
mesothelium and endothelium
blood cavities
Simple squamous cell shape
wider than they are tall
Simple cuboidal epithelial cells
found in many of the ducts
ex: parotid gland
Simple columnar cells
normally found in the digestive tract
Where is the brush border found?
normally in the gut
What is brush border made of?
actin
Pseudostratified epithelium
NOT stratified
all cells do touch the basement membrane
the nuclei are just at different heights
Connective vs. epithelial tissue
connective tissue is much less dense than epithelial
Stratified epithelia
multiple layers of epithelial cells but only the basal layer of cells rests on basement membrane
Stratified squamous
top layer consists of flattened cells
two types of stratified squamous
1) Keratinized
2) Non-keratinized
