A single cell within a culture of freshly isolated cardiac muscle cells is injected with a fluorescent dye that cannot cross cell membranes. Within minutes, several adjacent cells become fluorescent. The most likely explanation for this observation is the presence of
High-Yield Explanation
Gap junctions are pores composed of paired connexons that allow the passage of ions, nucleotides, and other small molecules between cells. Ref: katzung 12 th ed.