Cell Junctions

Question 1

What are the 5 types of cell junctions

Answer 1

Adherens Junctions, Gap Junction, Hemidesmosome, Desmosome, and Tight Junction

Question 2

Adherens Junctions

Answer 2

”belts” of plague run along the inside membranes of adjacent cells. Cadherin proteins span the space between the two cells and the cell membranes to anchor within the belts of plaque. Actin microfilaments also embed within the plaque belts.

Question 3

Gap Junction

Answer 3

Weakest physically of the junctions -not designed to withstand physical stress. A means of communication between cells. Connexin proteins span the membranes of the two adjacent cells to provide tunnels or pores for rapid transport of material between cells

Question 4

Hemidesmosome

Answer 4

“half” of a desmosome. On one side, it resembles a desmosome. But on the other hand, the integrins (not cadherins_ anchor into the areolar layer of the basement membrane - the connective tissue underlying epithelial cells. This junction binds a cell to a basement membrane, rather than binding two cells to each other

Question 5

Desmosome

Answer 5

“spot weld.” Two “spots” of plaque line the inside membranes of two adjacent cells. Cadherin proteins span the space between the two cells and the cell membranes to anchor in the plaques. Intercellular keratin(intermediate) filaments also anchor within the plaques.

Question 6

Tight Junction

Answer 6

“waterproof” junction between cells. Various transmembrane proteins “stitch” the two cell membranes together to prevent the passage of any fluid between the two cells.