L1: Organisation of the Human Body

Question 1

how do tight junctions keep cell polarity?

Answer 1

preventing migration of proteins between apical and basal surfaces

Question 2

where are tight junctions found?

Answer 2

• stomach
• intestines
• bladder

Question 3

how do tight junctions join the cytoskeletons of adjacent cells?

Answer 3

via ZO-1 to actin

Question 4

what is the function of adherens junctions?

Answer 4

prevent cell separation from tension forces like in contractions

Question 5

what are the proteins involved in adherens junctions?

Answer 5

• cadherins (span the gap)
• catherins (link cadherins to actin)

Question 6

less continuous epithelial cells are called…

Answer 6

adhesion plaques

Question 7

in some epithelial cells, adherens junctions are also…

Answer 7

belt desmosome or adhesion belts (zonula adherens)

Question 8

adherens junctions are more _____ located than tight junctions

Answer 8

basal

Question 9

what is the function of desmosome junctions?

Answer 9

resist shearing forces and link cell surface to keratin

Question 10

what are the proteins involved in desmosome junctions?

Answer 10

cadherin spans the gap and binds to desmoplakin

Question 11

where are desmosome junctions most common?

Answer 11

skin epithelium and cardiac cells of the heart to prevent pulling apart.