Intercellular junctions Flashcards
to know the things about the stuff v well ok
3 main types of intercellular junctions in animals
- Tight junctions
- Gap junctions
- Desmosomes
type of intercellular junction in plants
plasmodesmata
Tight junctions
-intercellular junctions in animals that bind cell membranes closely together
- function: prevent leakage of extracellular fluid + facilitate passage of ions/molecules through intercellular space (selective exchange of materials)
- Example: they make human skin water tight by preventing leakage of fluid between epithelial cells
Gap junctions, aka _________
*intercellular junctions aka “communicating junctions”
• Cytoplasmic channels between two cells
• Enables flow of information between cells
-letting in certain molecules/ions
-electrical impulses
Desmosomes, aka ________
*intercellular junctions aka “anchoring junctions”
• Function like rivets - they bridge the space between two cells and fasten them together
• intermediate filaments are the “anchors” on the inside of each cell
• Example: ruptured desmosomes are often the culprit of torn muscles
intermediate filaments
- strong, rope-like protein structures that are a component of the cytoskeleton
- various different protein subunits (different from its brethren complexes made of tubulin and actin)
* types of proteins depend on specialization of the cell - non-polar protein complexes
plasmodesmata
*only plants have this intercellular junction
• communicating junction – similar to GAP junctions
• enables cell-cell communication
• facilitates intercell molecular transport
• desmotubule
• cytoplasmic sleeve
desmotubule
a protein structure in a plasmodesmata junction that provides stability/structural support
cytoplasmic sleeve
the fluid-filled space (in plasmodesmata) on either side of desmotubule and between adjacent cell membranes
cell junction
specialized points of fusion between two cells in direct physical contact
• facilitate communication
• bind cell membranes
• control intercellular flow of molecules
