AP BIOLOGY

Detailed explanation-1: -Gap junctions are specialized intercellular connections between a multitude of animal cell-types. They directly connect the cytoplasm of two cells, which allows various molecules, ions and electrical impulses to directly pass through a regulated gate between cells.

Detailed explanation-2: -Gap junctions are clusters of intercellular channels that allow direct diffusion of ions and small molecules between adjacent cells. The intercellular channels are formed by head-to-head docking of hexameric assemblies (connexons) of tetraspan integral membrane proteins, the connexins (Cx) (Goodenough et al. 1996).

Detailed explanation-3: -Gap junctions are channels that physically connect adjacent cells, mediating the rapid exchange of small molecules, and playing an essential role in a wide range of physiological processes in nearly every system in the body, including the nervous system.

Detailed explanation-4: -Gap junctions allow the exchange of ions, second messengers, and small metabolites between adjacent cells and are formed by two unrelated protein families, the pannexins and connexins.

Detailed explanation-5: -Combined with cell adhesion molecules and extracellular matrix, cell junctions help hold animal cells together. Cell junctions are also especially important in enabling communication between neighboring cells via specialized protein complexes called communicating (gap) junctions.