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Flashcards in Intercellular junctions Deck (10):
1

3 main types of intercellular junctions in animals

• Tight junctions
• Gap junctions
• Desmosomes

2

type of intercellular junction in plants

plasmodesmata

3

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

4

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

5

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

6

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

7

plasmodesmata

*only plants have this intercellular junction
• communicating junction – similar to GAP junctions
• enables cell-cell communication
• facilitates intercell molecular transport
• desmotubule
• cytoplasmic sleeve

8

desmotubule

a protein structure in a plasmodesmata junction that provides stability/structural support

9

cytoplasmic sleeve

the fluid-filled space (in plasmodesmata) on either side of desmotubule and between adjacent cell membranes

10

cell junction

specialized points of fusion between two cells in direct physical contact
• facilitate communication
• bind cell membranes
• control intercellular flow of molecules