Epithelia Flashcards
Where are stratified cuboidal
salivary glands and sweat glands
Where are stratified columnar located
male urethera
What are the three main specialisations on the surface of epithelial cells
The presence of microvilli, cilia or the presence of the protein keratin
pseudostratified cells are found where?
Variations between short and long cells but are all attached to the BM, these cells line the conducting part of the airway
What are the functions of epithelia cells
absorption
secretion
selective/protective barrier
transportation
Where are simple cuboidal cells found
good for secretion and absorption so therefore is found in the liver and the kidneys
Simple columnar
Good for secretion and absorption therefore are found in the GI tract
Stratified squamous - where are these found?
Used in protection do therefore line the oesophagus and epidermis
What are the two vital functions of tight junctions
they prevent the passage of molecules and ions through the spaces between cells
They block the movement of integral cell membrane proteins between apical and basolateral surfaces of the cell
Simple squamous
Lines the capillaries and blood vessels to allow rapid diffusion
Zonula Adherens
completely encircles each cell providing stability, holding the cells in a tissue together.
Transitional where the apical layer is cuboidal
bladder
desmosome
a type of junction which strengthens cell links
Gap junctions
tiny pores to allow passage of small molecules between adjacent cells (these respond to stimuli as a unit)
mesothelium
epithelia that surrounds the body cavities (pericardium, peritoneum and the pleura)
what is the endothelium
lines the walls of blood vessels
functions of the endothelium
Controls the passage of substances in and out of the cell
Assist in forming the BM
control blood pressure
angiogenesis (formation of blood vessels from pre-existing blood vessels)
role in acute inflammation
What happens to the endothelium in the presence of histamine
endothelial cells lose attachment to each other and retract, allowing fluid and proteins to diffuse out into the local tissues causing tissue swelling termed oedema. This reorganisation of cell-cell junctions is rapid and reversible and takes place in the space of a few minutes (e.g. insect sting).
fenestra
These are windows/gaps between individual endothelium cells. These allow large molecules to move between the blood and surrounding tissues (found for example in the endocrine glands)
Tell me about the mesothelium
Provides a friction free surface by secreting a watery fluid which facilitates movement of an organ within a cavity. these also form the serous membranes known as pericardium, peritoneum and pleaura.
