Tissue organisation revision Flashcards
nuclear pore
made of subunits - annular, luminal, ring and column
perinuclear space
space between the inner and outer membrane of the nuclear envelope
relationship between the perinuclear space and the ER lumen
continuous
where is peripheral heterochromatin
lines the inner side if the nuclear envelope
difference in morphology between rough and smooth ER
rough is flattened
smooth is tubular
a stack of ERs is called a…
cisternae
size of vesicles from the golgi
they contain macromolecules and are >50nm
diameter of microtubules
20nm
what are microtubules made of
polymers of alpha and beta tubulin
intermediate filaments
connect desmosomes via cytokeratins
concerned with mechanical strength and stabilisation of the nuclear envelope
each cell type has a different kind of IF
polymers of filamentous proteins forming rope like structures
types of intermediate fibres
cytokeratins
vimentins
neurofilamentous proteins
microfilaments
filamentous (F-actin) or monomeric (G-actin)
most dense in the periphery
sarcomas
cancers of the mesenchymal cells
examples of mesenchymal cells
fibroblasts, osteoclasts, chondrocytes
cell to cell junctions
zonulae - continuous belts eg tight junctions and adhesion belts
maculae - discrete spots eg desmosomes
action of tight junctions
seal paracellular pathways
regulation of cell polarity
adhesion belts
basal to tight junctions function as master junction cadherins associated with adhesion belts interact with actin microfilaments
does mitosis occur in absorbative epithelia
yes
cells undergo constant renewal from crypts
where is exocrine solution from
luminal plasma membrane
