In intestinal epithelial cells, the different plasma membrane domains are separated from each other by special barriers. Indicate true (T) and false (F) statements below regarding this separation. Your answer would be a four-letter string composed of letters T and F only, e.g. FFFF.
( ) These barriers are set up by nanoscale lipid raft domains.
( ) Proteins normally cannot pass through these barriers, whereas any membrane lipid can do so freely.
( ) The asymmetric distribution of membrane proteins resulting from these barriers is functionally important.
( ) These barriers are a result of proteins of the apical surface forming a large aggregate together that excludes proteins of the other domains.

Question

In intestinal epithelial cells, the different plasma membrane domains are separated from each other by special barriers. Indicate true (T) and false (F) statements below regarding this separation. Your answer would be a four-letter string composed of letters T and F only, e.g. FFFF.
( )	These barriers are set up by nanoscale lipid raft domains.
( )	Proteins normally cannot pass through these barriers, whereas any membrane lipid can do so freely.
( )	The asymmetric distribution of membrane proteins resulting from these barriers is functionally important.
( )	These barriers are a result of proteins of the apical surface forming a large aggregate together that excludes proteins of the other domains.

Quizplus · Accepted Answer

The barriers are set up by special cell-cell junctions known as tight junctions, which limit the diffusion of proteins (and mostly the lipids in the extracellular monolayer) of the plasma membrane between the apical and the basolateral domains.

In Intestinal Epithelial Cells, the Different Plasma Membrane Domains Are