Epithelial Cell-Cell Junctions

Question 1

Functions of Tight Junctions

Answer 1

• barrier separating ‘OUT’ from ‘IN’
• restrict paracellular permeability
• cell membrane polarity
• actin-associated
• segregate the apical-basolateral domains

Question 2

Function of Adherens Junctions

Answer 2

cell-cell adhesion

Question 3

Function of Desmosomes

Answer 3

mechanical support of the tissue

Question 4

Functions of Gap Junctions

Answer 4

• holds regions of the Lateral Membrane closely together
• direct cell-cell communication
• limited cytoskeleton association

Question 5

Features of Tight Junctions

Answer 5

integral proteins
Proteins: occludin, claudins, and JAMS
ZO-1 and ZO-2 linking TJ to actin cytoskeleton

Question 6

Features of Adherens Junctions

Answer 6

E-Cadherins
β-catenin
α-catenin

Question 7

Features of Gap Junctions

Answer 7

connexins (channel proteins)

Question 8

Locations of Tight Junctions

Answer 8

boarder between apical and basolatermembranes

Question 9

Locations of Gap Junctions

Answer 9

lateral membrane

Question 10

Locations of Adherens Junctions

Answer 10

close to the apical membrane

Question 11

Locations of Desmosomes

Answer 11

found in cardiac muscle tissue, bladder tissue, gastrointestinal mucosa, and epithelia
cytoplasm
anchor cells together