Myocardial cells are joined to adjacent myocardial cells by  

Options

A. tight junctions
B. desmosomes
C. gap junctions and electrical synapses
D. microvilli

Answer

**Step-by-Step Solution:**

1. **Identify the Type of Cells**: Myocardial cells are also known as cardiac muscle cells, which are specialized cells responsible for the contraction of the heart.

2. **Understand the Structure**: Myocardial cells are interconnected through structures known as intercalated discs. These discs are crucial for the function of cardiac muscle tissue.

3. **Function of Intercalated Discs**: Intercalated discs serve two primary functions:
- They hold adjacent myocardial cells together, providing structural integrity.
- They contain gap junctions that allow for the diffusion of ions between cells, facilitating rapid transmission of electrical impulses.

4. **Identify the Correct Answer**: Among the options provided (tight junction, desmosome, gap junction, electrical synapse, microvilli), the correct answer is gap junctions. These structures are part of the intercalated discs and are essential for the communication between myocardial cells.

5. **Conclusion**: Therefore, myocardial cells are joined to adjacent myocardial cells by gap junctions, which are crucial for the synchronized contraction of the heart muscle.

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