Gap junctions at intercalated discs provide which kind of coupling?

Gap junctions at intercalated discs provide which kind of coupling?

• A. Mechanical coupling
• B. Electrical coupling
• C. Chemical coupling
• D. Structural coupling

Answer: (B)

Gap junctions in cardiac intercalated discs enable electrical coupling. They form direct cytoplasmic channels between neighboring cardiomyocytes, allowing ions (like Na+, K+, Ca2+) to pass rapidly from cell to cell. This creates a low-resistance pathway for depolarization to spread, so the heart muscle contracts in a coordinated, synchronized manner. While the intercalated discs also include desmosomes and adherens junctions that provide mechanical coupling to hold cells together, gap junctions specifically mediate the electrical connection that coordinates heartbeat.

Gap junctions in cardiac intercalated discs enable electrical coupling. They form direct cytoplasmic channels between neighboring cardiomyocytes, allowing ions (like Na+, K+, Ca2+) to pass rapidly from cell to cell. This creates a low-resistance pathway for depolarization to spread, so the heart muscle contracts in a coordinated, synchronized manner. While the intercalated discs also include desmosomes and adherens junctions that provide mechanical coupling to hold cells together, gap junctions specifically mediate the electrical connection that coordinates heartbeat.