Question

Compare the following cell junctions: Tight Junctions, Gap Junctions.

Answer 1

On the basis of location
Tight junctions are found only in epithelial cells, while, gap junctions are found to be distributed all over the body.

On the basis of function
Tight junctions are barriers formed between the extracellular space to prevent the transport of substances via the gap between the boundary of two cells. Very contrastingly, gap junctions actually connect two cells together to make a passage that allows molecules to pass between them.

On the basis of space in between
Tight junctions, virtually speaking, are said to leave no space or gap in between the cells, while, gap junctions are defined to have close to a 2 nm gap in between two adjacent cells.

On the basis of composition
Tight junctions are known to consist of proteins called claudin and occludin aggregating together and associating with other zonula proteins. Gap junctions on the other hand, consist of connexin proteins.