Final answer:
Desmosomes are cell structures acting as 'spot welds' that use cadherins, specifically desmogleins and desmocollins, to join animal cells. This connection provides strength to tissues, especially those subject to stretching.
Step-by-step explanation:
Desmosomes, also known as adherens junctions, are crucial for the structural integrity of tissues in animal cells. They act as 'spot welds' by firmly adhering cells to one another. The cadherins involved in desmosomes are specialized adhesion proteins that differ from those in other cell junctions both in domain structure and function. Specifically, the cadherins in desmosomes are called desmogleins and desmocollins, which both cross the cell membranes to connect with intermediate filaments such as keratin in the cytoskeleton. This results in a robust intercellular bond, providing strength to tissues subject to mechanical stress such as skin, heart, and muscles. Despite being tight bonds, desmosomes allow fluids to pass through the intercellular spaces.