Final answer:
B. False
Desmosomes do not form channels for electrical stimulation in cardiomyocytes; rather, it's the gap junctions in cardiac muscle that allow depolarizing currents to flow between cells for coordinated contraction. Desmosomes provide structural support.
Step-by-step explanation:
The statement that desmosomes form channels that allow each cardiomyocyte to electrically stimulate its neighbors is false. In cardiac muscle, gap junctions are responsible for forming channels that allow the depolarizing current to flow from one cardiac muscle cell to the next, facilitating the transmission of action potentials and the coordinated contraction of the heart. Desmosomes, on the other hand, serve a different function in the intercalated discs of cardiac muscle fibers. They act as structural anchors, holding the ends of cardiac muscle fibers together so that they do not pull apart during contraction.