Final answer:
Gap Junctions are the intercellular junctions in animal cells that allow for the rapid transport of ions and small molecules, thereby enabling cell-to-cell communication.
Step-by-step explanation:
The intercellular junction that allows for the rapid movement of small molecules or ions to flow from one animal cell to the next is the Gap Junction. These junctions consist of protein-lined pores that enable electrical and metabolic coupling, coordinating functions within a group of cells by allowing substances like ions, nutrients, and other small molecules to pass directly between the cytoplasm of adjacent cells. Unlike desmosomes, which adhere cells together, and tight junctions, which form watertight barriers, gap junctions act as channels and facilitate communication and cooperation among cells within tissues.