Question

Cardiac muscle acts as a syncytium due to the presence of _______ and _______ found in intercalated discs?

1) Desmosomes and gap junctions
2) Tight junctions and desmosomes
3) Gap junctions and tight junctions
4) Adherens junctions and gap junctions

Answer 1

Cardiac muscle functions as a syncytium due to desmosomes and gap junctions in intercalated discs, with gap junctions facilitating electric coupling and desmosomes providing structural integrity.

Step-by-step explanation:

Cardiac muscle acts as a syncytium due to the presence of desmosomes and gap junctions found in intercalated discs. The correct answer to the question is option 1) Desmosomes and gap junctions.

Intercalated discs contain gap junctions that allow the depolarizing current produced by cations to flow from one cardiac muscle cell to another, facilitating electric coupling. This rapid transmission of action potentials enables the coordinated contraction of the entire heart. Meanwhile, desmosomes function to anchor the ends of cardiac muscle fibers together so that the cells do not pull apart during the stress of contraction, reinforcing the structural integrity of the heart muscle during its powerful contractions.

Answer 2

Cardiac muscle acts as a syncytium due to the presence of desmosomes and gap junctions found in intercalated discs (Option 1).

Step-by-step explanation:

Cardiac muscle acts as a syncytium due to the presence of desmosomes and gap junctions, which allow for coordinated contraction and maintain cell integrity.

These structures are crucial for the heart's functionality. Gap junctions create channels that allow for the rapid transmission of action potentials between cardiac muscle cells, facilitating coordinated contraction of the heart. Desmosomes provide the mechanical strength to maintain cell integrity during contractions, anchoring the ends of cardiac muscle fibers together.

Thus, the correct option is number 1.